I agree with this for the most part, but The Big Bang Theory is a bad example imo. It is still laughing at geeks, not with them. I think that's why it rubs a lot of people (myself included) the wrong way.
Like, they've both got the stereotypical awkward Indian engineer who can't talk to women, but SV took a novel approach by not hating him. SV's weird-by-engineering-standards characters are weird for reasons outside of their nerdiness (e.g. Jared's German-language night terrors), BBT just turned Sheldon's nerdiness up to 11. (And created a really nasty autism stereotype in the process.) And so on.
(Can anyone imaging BBT finding a stereotype as obscure as Gilfoyle's occultist thing? Because that's definitely a 'thing', but it's some serious inside baseball.)
If anything, you might argue that the transition from Big Bang to Silicon Valley is a display of the changing position of nerds. More realistically, though, I think they're just aiming at different demographics.
It's usually a disaster when writers try to create characters smarter than themselves. You get word soup based on how the writer imagines smart people communicate, filled with weakly used jargon and unnecessarily long words.
My coworkers still accuse me of using complex language even though I have worked to simplify and clarify my communication.
Although, strategically, we should be supporting the "nerd black face" image.
Of course you are.
The jokes are validated by David Saltzberg, a Professor of Physics and Astronomy at UCLA.
I think if the jokes were superficial and lazy, I would perceive that as mean-spirited. But they seem to get the details correct.
The Heisenberg uncertainty joke was pretty good. https://youtu.be/F6LIo-FfpKs?t=11s
The characterizations, meanwhile... well, Howard and Sheldon both struck me as pointlessly mean-spirited portrayals, while Rajesh was just a really overwrought stereotype. It felt like the technical side of things ended at input on specific jokes, and in response everything else was hammed up to ensure it would maintain mass appeal.
Of course, that's a pretty common pattern - could-be-good works getting diluted to ensure they won't drive away any viewers. I wouldn't be surprised if it boils down to a good idea plus executive meddling. The later seasons also seem to have a really bad case of Flanderization, where writing novel jokes got hard so "hah, nerdy talk!" came to the fore.