Yudkowsky's outfit is the Machine Intelligence Research Institute, not the Singularity Institute. The latter might be Bostrom? Can't recall.
MIRI was, until 2013, called the Singularity Institute for Artificial Intelligence. Apparently the name change was part of a deal with Singularity University to avoid brand confusion. Announcement here:
https://intelligence.org/2013/01/30/we-are-now-the-machine-i...
Thank you.
Thiel was an early backer of SI and attendee of the Singularity Summits that ran from 2006-2012.
https://en.wikipedia.org/wiki/Singularity_Summit
Soon after that, awareness of AI and superintelligence went mainstream, and we got FHI, FLI, etc.
I don't know if Thiel backs MIRI as he did SI. Arguably, he doesn't need to. He made his money on DeepMind and helped trigger a larger movement, and other institutions with a lot more resources, like Alphabet and MSFT, carry forward the torch.
Thiel wasn't an attendee, he was one of the people running the conference
And the vision of what AI was becoming was voiced much earlier by Yudkowsky, whose Singularity Institute received funding from Thiel.
If anything, they heard what a few prophets were shouting. They saw some early demos in a startup pitch. They responded and DeepMind's work soon became as public as AI research is. That is to say, most people ignored it until the Google acquisition.