Ideally, a client app would make these backups for you automatically. I hope Bluesky official client will add automatic backups (in addition to the existing manual export flow that already exists). It's not hard to set it up as a GitHub action today if you're technical but making it accessible to non-technical users seems important.

>Can i run multiple PDSes with my own single identity to not give one provider exclusive power over access to "my" data?

Not really since there has to be a source of truth where the writes happen. I guess you could manually replicate changes between multiple servers but there still has to be one that applications know to talk to. I'm not sure what problem it would solve. This seems similar to "can I have multiple deployments of my site" — you sure can, but you might as well deploy it elsewhere when you actually plan to point to it.

I personally believe that the chance of Bluesky PBC suddenly swapping all of their software to no longer be built on atproto to be a very low chance, yes.

There’s middle grounds here; for example, due to some recent moderation decisions, some users have decided to move away from Bluesky PBC-run PDSes and to self hosting. Those users did not need to proactively backup to move. The proactive backup cases are things like “Bluesky PBC’s servers disappear suddenly” or “they ban your account.”

I don’t think you can run multiple PDSes, but since it’s quick to move the canonical version, I don’t see that as a huge drawback personally. In the same way you’d fallback to the secondary if the primary turns out badly, you’d set up a new PDS and point your identity at it.