If anything worried me it would be fundamental research more than startups -whether the new admin affects fundamental researchers coming in would be a bigger issue than a few entrepreneurs having to work harder at home. Missing up on start-ups is not all that. Uber, AB&B, etc. are nice to haves, but aren't making fundamental discoveries --they are changing how we use resources we already have rather then providing new things.
Don't worry so much. You have a mortal lock on the pipeline of first-time tech founders, and your cycles are overwhelmingly populated by graduates of US and European universities. Yes, a fair number of talented people from disfavored west Asian countries won't be able to start up here. That's OK: because of the way venture capital works, and because of YC's role in it, they really won't be able to start at all, and you won't have to compete with them.
Sure, they'll remain outside the US as a nucleation site for new startups that could have in theory challenged US dominance in technology startups. But the US controls the financial energy. They won't get anywhere.
Startups will survive large-scale institutional bigotry just fine. In fact: some of them will even profit from it.
"because of YC's role in it, they really won't be able to start at all"
Not sure what the reasoning is here. How is YC doing anything to block people from starting companies? You don't lose anything by getting rejected from YC, other than the few days spent applying.
YC is just the beneficiary of the status quo. If they disappeared one of the lesser players would just take their spot in line. But the real status quo edge, the real big deal here, is the ability to get rich without actually making any money, i.e. unprofitable growth at scale (minus profits). This is a real, real big deal, but you can't do it without access. You can turn an honest buck anywhere. Making a bundle without actually turning a profit is extraordinarily hard to do outside of Silicon Valley.
The startup ecosystem is heavily based on gatekeeping and validation by existing players - YC is one of many (but one of the most influential) in this space.
To be a bit simplistic, I think Thomas' point is that the likelihood of tech startups outside of the traditional US-centric startup ecosystem succeeding is very low, due to lack of funding and the general consequences of being an Outsider to the Silicon Valley elite.
YC's role in it is, of course, being one of the most influential players that control which ideas get funded/attention, and which do not.
Even physically outside of the US, the startup ecosystem is still overwhelming reliant on US money. Which is to say even if there is an appetite for funding founders in these disfavored countries, regulations (or simple politics) may prevent it.
That said, I do disagree somewhat - US/European money is not the only source of venture capital dollars. I suspect at least some of the founders we're losing here will be able to start their companies with Chinese money. The loss of this talent pool will contribute - in a small way right now, but snowballing as time goes on - to the loss of US-centric economic hegemony.
There are certain kinds of businesses - drug discovery - say, that take years and years to become profitable. It's not really possible to start them without a lot of capital. Not everything SV does is that way, but many companies are.
Don't be naive. If you're not in with the cool kids, then you don't get invited to the cool parties. That's not a criticism of YC, it's just the social reality.
Contrary to popular belief, it is in fact possible to grow a startup without VC money. Perhaps not all types, but certainly a bigger subset than people tend to admit.
