Demis Hassabis and Geoffrey Hinton Awarded Nobel Prizes

One of the problems with the Nobel Prize as a measurement or criteria is that it is not really suited for that by nature, especially given criteria like no posthumous awards. This means that it is easy to critique awarding a Nobel Prize, but it is harder to critique not awarding one. You can't give a Nobel Prize to the inventor of the engine, because they probably died a long time ago; you could have for a recent kind of engine. Similarly, you could give a Turing Award to the inventors of C (and they probably did) but the first person who created a mnemonic shorthand over raw machine opcodes during WWII or whatever was probably dead before the Turing Award was even created.

Let's take your 'inventing the LED' for example. You seem keen on interpreting the absence of a Nobel Prize here as a relative judgment about 'inventing LEDs' vs 'inventing blue LEDs'. But you don't establish that there is any reason to think this is one of the cases where the lack of an award can be validly interpreted as a snub & a judgment by the relevant committee. Is it?

Well, let's take 5 seconds to check some of the historical context here, like who would you award a prize to? I open up Wikipedia and I check the first three names. (Why three? Because Nobel Prizes are arbitrarily limited to 3 awardees.)

All 3 of them, including Oleg Losev who is described as physically creating the first bona fide LED and so seems to be the closest to "the inventor of the LED", died before or around the first commercial LED being announced (October 1962). For about a decade, early weak expensive red LEDs "had little practical use", until finally they began to replace nixie tubes. Only then did they start to take off, and only then did they start to become a revolution. (And reading this WP history, it seems like blue LEDs have wound up being more important than the original red ones anyway.)

Oleg Losev in particular died in 1942, in obscurity, and given the year, you won't be too surprised why:

Losev died of starvation in 1942, at the age of 38, along with many other civilians, during the Siege of Leningrad by the Germans during World War 2.

You can't award Nobel Prizes to the dead - and by the time it was clear LEDs were a major revolution, many of the key players were well and thoroughly dead. That is, the committee could not have awarded a Nobel Prize for 'inventing the LED', without either being prescient or awarding it to later researchers, who were lucky enough to be long-lived but did not actually invent the LED, and that would be a travesty on its own and also crowd out meritorious alternative physics breakthroughs (of which there were many in the 20th century that they are still working their way through).

So, this is one reason to not put too much stress on the absence of a Nobel Prize. Not having a Nobel Prize for work in the early-to-mid 20th century means in considerable part things like "was not killed by Hitler or Stalin", things which are not particularly related to the quality or value of your scientific research but are related to whether you can survive for the 20 or 40 years it may take for your Nobel Prize to show up.