Here as a post on his blog from 8 years ago: https://blog.samaltman.com/the-software-revolution

"...development of an AI that could end human life may only require a few hundred people in an office building anywhere in the world, with no equipment other than laptops.

The new existential threats won’t require the resources of nations to produce."

and

"The fact that we don’t have serious efforts underway to combat threats from synthetic biology and AI development is astonishing."

So (2) could be a factor, for sure. But (1) is consistent with what seems to have been his viewpoint for a long time. It's possible he's updated his viewpoint and is faking concern about safety, but given how recent advances have seemed to make a lot of people more concerned, I don't think that's likely.