All the media coverage is causing fewer people to apply for visas, so it might actually be easier than before to get a visa (not kidding). Canadian universities are seeing 500% increases in applications, even tourism is down, because of exactly this sort of worry.
The fear is enormous, but the actual changes are small, ergo, could be easier to get a visa now.
It has already impacted tourism and international student enrollment in colleges. Logically, business creation would follow. Canada is reaping the benefits. Tourism is up 20% and college enrollment is up by significant percentage as well.
We moved to SV in June from Switzerland to start a company. Is Switzerland overall a better place to live? Of course. But SV is still the best place to start a business. Trump luckily didn't impact that. And I don't think he can.
There were numbers released recently that showed that tourism since 2015 in top destinations increased - with the exception of 2 countries where it declined (Turkey, and USA).
Anecdotal, but: I myself turned down a job offer in SV in part due to Trump. When asking 4 random co-workers, none seem keen to move to the US, 2 of them even citing safety concerns (they are minorities from India and Africa and heard horror stories of former colleagues still in the US).
It's quite obvious that he's intend to reduce immigration. That's not likely an immediate problem for white founders from Europe. But there's obvious potential in Africa, the Middle East, or Asia. And it's crystal clear that if Trump gets his way, Elon Musk would have a rather hard time getting permanent residency in the US.
Apart from these actual, specific challenges, emigrating is a huge step for most people. The general hostility against "strangers" would definitely make me think twice about moving to the US today, even though I once spent a year in the Southwest and had a wonderful time.
Just dealing with customs officers at the airport has become a nightmare over the last decade: Being fingerprinted like a criminal is the most obvious change. But I've lately noticed that the attitude more and more resembles the thuggishness usually associated with police states. They have always had all the power, but lately they seem to relish to show it to you. Need 10 seconds to find your flight number? "Go to the back of the line, NOW, and try again with the respect the greatest country on the face of the earth deserves". (actual quote).
I'd be interested to know which European countries? And does it vary by the nationality of the visitor[1]?
[1] For the USA for example, Canadians visiting for business or tourism (an implied B1 or B2 visa, respectively), are exempt from fingerprinting. Canada is the only exception to the USA's fingerprinting rules.
With Bannon gone, I think the only immigration hard-liners left in Trump's circle are Stephen Miller and his chief of staff John Kelly who could very easily quit before ICE has a chance to wreck YC. Whitehouse Chief of Statff is a notorious high-turnover position and Kelly apparently threatens to quit on a weekly basis.
Anyway, YC never threw Thiel under the bus so maybe they can call in a favor if things get dicey?
Also, in case foreigners get accepted to YC, will it be more difficult than before to be able to stay in the USA for the duration of the program?