I essentially didn't have a private key prior to Keybase, and I think it's still the only place I use it, so I'll end up rolling a new one if Keybase becomes fundamentally untrustworthy.
They are fundamentally untrustworthy. They haven't taken security issues in the past very seriously, they also have ties to China.
That’s Zoom. Post acquisition Keybase is tied to some of those, but not all. Their dev team is not going to move to China (at least not immediately) and past security issues in Zoom are no indication of Keybase safety.