This may be a shock to you, but California, Washington, Massachusetts, New York, and Texas have small businesses and rural areas, too.
And GitHub accounts are not a particularly good proxy for "all developers." Many, many developers work in non-tech companies doing line-of-business software that will never see the outside of the building.
It may still be true that a majority of US developers live in those states, but that does not at all mean that political and societal shifts that affect developers are only something that happens on the coasts. (Hell, Texas isn't even on the East or West Coast—and I've literally never seen anyone talk about "coastal" people in that context and mean "Gulf Coast".)
And all of that is before even addressing your attempt to imply that not having a software startup that's comparable to two of the most influential recent startups is in some way indicative that an area's tech worker population isn't worth considering. That's on par with people thinking Apple is "doomed" because it doesn't come out with a new product as revolutionary as the iPhone every year. "Not the absolute top of the top" is not the same as "totally unworthy of attention".
Nothing compares to OpenAI at the moment. That argument is a classic example of false equivalence — to draw the two largest valley centric examples and the fastest growing company in the history of the Internet and ask me to find equivalence is asinine and a fools task.
It’s further false argument to say “the majority of developers are on the coasts”
when the contention is whether there are successful companies elsewhere. The location of software engineering talent density will follow venture market funding availability, not companies that represent non-coastal success stories where that PE and VC money concentrates workers.
My original comment is that the 2017 tax bill hurt the coastal masses. That's it.
You then stated that there are software programmers everywhere and startups everywhere. I followed up with most programmers and startups are along the coast.
Not sure with what you disagree. It's like when State and Local Taxes were limited. It hurt California residents more than Idaho residents. It's not only coastal states but more costal states than non coastal states.