When I started to notice the negative campaign ads about Masters before the election, he looked vaguely familiar. I wondered if I saw him at Alcor's conference back in June.

This article from several years ago makes Masters sound like a transhumanist, though since then he has married, started a family and identifies as Catholic:

https://harpers.org/archive/2015/01/come-with-us-if-you-want-to-live/

From the article:

Some months later, I came across the Tumblr of Blake Masters, who was then a Stanford law student and tech entrepreneur in training. His motto — “Your mind is software. Program it. Your body is a shell. Change it. Death is a disease. Cure it. Extinction is approaching. Fight it.” — was taken from a science-fiction role-playing game.