He didn't call them "fake news", he called them leftist media sources and that's a factual statement. The Guardian especially is anything but a neutral source.
(They also publish opinion pieces from other positions/ideologies, but that's a part of the whole liberal free market of ideas thing.)
The newspaper's reputation as a platform for liberal and
left-wing editorial has led to the use of the "Guardian
reader" and "Guardianista" as often (but not always)
pejorative epithets for those of left-leaning or
politically correct tendencies.
Are you disputing the quotations attributed to Thiel in the reporting? No, you don't seem to be.
You asked for examples of toxic viewpoints held by Thiel, someone delivered, and you plugged your fingers in your ears and said "lol facts don't matter". Don't be that guy.
Now, he may well be a white supremacist (although I haven't heard any complaints from his Jewish cofounders, FWIW), but these do not prove it at all.