One hub, or many?

I think there's likely a pretty big selection effect on who posts in these discussions about community, because the only reason I'm even here to comment at all is that the in-person rationalist community helped me build the confidence to do so. Before moving in with the LW team, I was so shy and low-self-esteem that I didn't think myself worthy to even talk to the people whose names I'd seen online. I spent the last two years of college wishing desperately for the return of the rationalists I knew who had all up and moved to the Bay, but never once reaching out to them, because I didn't feel like I was smart or cool enough to be worth their time. The first time I posted on LW I was so nervous that I cried for an hour before pressing submit, and I only got to that point in the first place because someone was sitting next to me giving me encouragement and basically holding my hand through all of it.

I'm also not good at making friends online and don't enjoy spending much of my time interacting online, so for the people who have said that they get plenty of value out of just being part of the rationalist community online, well, that wouldn't work for me either. 

The problem with your last question - about meeting other smart nice sane people - is that you're assuming I would have met people otherwise. My expectation after college was that I'd move to a new city and basically spend all of my time alone, just like I had for most of my life up to that point. I'd make friendly acquaintances at work and then come home to an empty apartment, forever. If I got lonely I could call my mom.

Instead I moved to the Bay (yes, solely to be part of the rationalist community) and into a rationalist group house. I'm not a techie, I didn't have a job lined up, and I only knew a couple people in the community, and those not very well. Being thrust into that social environment headfirst was really important for me, because I don't think I ever would have gotten over the social hurdles of interacting with rationalists otherwise and would have spent the rest of my life pretty lonely - or else just moved back to my hometown, which is what my sister and almost all of our friends ended up doing.

Also, I knew a lot of nice, smart, sane people at my elite college, and I was friends with them, but there was always something missing. Rationality was a big part of my life long before I ever met other rationalists, and it was exhausting to have to re-explain AI risk, transhumanism, and the basic definition of rationality any time I wanted to talk to someone about the things I cared about. 

It also wasn't until I moved to the Bay community that I ever felt I was surrounded by people who were better than me. Growing up I was always the smartest kid in the room, and in college, I was more thoughtful and more altruistic than the people around me, and I was better at dealing with my own problems and directing my own actions than most adults I knew. As a result there were very few people for me to learn from, something that was disappointing and isolating for my entire life. That feeling has completely disappeared since I moved here; I'm always being pushed to become better by the people around me.

Is the Bay area rationalist community really all that great as a social group compared to just meeting the smart nice sane people who live in every town?

I'll say the one big advantage here is pre-existing shared context. I can walk into a rationalist or EA party or other space and just already have a ton in common with the other people there. We have natural things to talk about, and there's some useful amount of pre-vetting that happens via a self-selection process that seems to shed many of the "smart nice sane people" would are otherwise fairly incompatible with much of rationality and EA (for example, high contextualizers who are uncomfortable talking about ideas in isolation from the social consequences of talking about those ideas).

I also think centralization in Berkeley causes damaging PR problems, and that this is a significant point in favor of many hubs.  But that's in a comment because it deserves separate attention and may invite passionate response.

A story:
I was rationalist adjacent for a long time, but I never spent much time on LessWrong.com or felt like a member of The Rationalist Community.  Partly, I was intimidated by the posters here and had (still have) some pretty core philosophical disagreements.  But a lot of it was because every time I came here or to any other rationalist's blog, I would see a bunch of obliquely-referenced personal drama and inside baseball stuff about the community in Berkeley.

Eventually, Scott's SSC Meetup Everywhere post convinced me to check out my nearest group.  I met some really cool people, who were a lot more normal and friendly than I'd been led to expect.  Now I run a meetup in my local city, and do some outreach.  I'm pretty sure that I'm the kind of person who's a really good fit for joining the cause, the kind we want more of.  But I didn't know it from the online community.

Rationality is already pretty weird, and rationalists tend to be quirky people.  But my experience visiting and reading about Berkeley is that merely living there encourages one to spend freely and frivolously on weirdness.  (I mean this of the city generally; not the rationality community there, whom I've never met and know only by reputation.)  If you want to raise a kid and live together in a single house with your 5 best friend-and-sexual-partners, it's no business of mine.  For all I know, I'll be thanking you in 100 years for discovering the optimal living arrangement.  But it's a very Berkeley thing, which leads to very Berkeley problems, which all tend to be viewed pretty negatively by the outside world.

To the extent that rationalists centralize in Berkeley, public forums become largely Berkeley-specific forums, in which weird, Berkeley-specific problems (social drama, weird living arrangements, etc.) are a normal and noteworthy topic of discussion.  Even if there's not frontpage posts, it leaks out into the public through comments and offhand mentions in discussions about rationality.  And that weirdness and drama leakage can really turn people off from the movement who aren't in Berkeley, even when they're really attracted to rationality as a practice and movement.

So, people most qualified to build community and organize meetups often happen to be people who want to do more than merely build community and organize meetups. They often want a community-adjacent job, and they move where such jobs exist.

To have sustainable rationalist communities outside of Bay Area, we need one of the following:

a) people qualified to build community and organize meetups, who are not interested in this type of job;

b) sufficiently large local community so that there are enough replacements for the people who leave;

c) community-adjacent jobs outside of Bay Area;

d) remote work in the community-adjacent jobs.

It could be different solutions for different cities. Option (a) is a question of luck, whether you have such people in your city. Option (b) is a chicken-and-egg problem, if you don't already have a large community, it gives you no advice how to create it. Option (c) is what people in given city should think about. Option (d) is how people already in Bay Area can support them.