Regarding that, I read this:
Mr. Buffett declined to comment on the Stone deal. Its entirely Todds, said Debbie Bosanek, Mr. Buffetts assistant, in an email. He never comments on anything that Todd or Ted do. They have total autonomy.
Maybe he himself isn't as open. Either way, just because they started investing at fintech doesn't mean they'll jump right into crypto. Fintech is already risky by their standards, it would seem, so I would expect them to only take one step at a time.
Either way, crypto doesn't need Warren Buffett's approval.
I assumed it wasn't him holding the reigns on this decision. He isn't a tech guru especially not informed enough in tech to focus on startups that go flop constantly in this industry.