When imperfect systems are good: Bluesky's lossy timelines

If everything good is assumed to eventually become bad, why not use things while they are good and then immediately move on when it becomes bad?

Not everything good becomes bad. That premise is wrong.

Bluesky accepted VC money. For a social platform that means its death certificate has already been signed.

What you're ignoring with that framing is that we can use social media that operates outside the VC startup pipeline and doesn't have enshittification baked in from the start.

Your actions' consequences are not limited to benefiting from the thing like it would for a product - with social media, you improve the networking effect for the soon-to-be bad. (Nothing against bluesky, I don't know or think it will do so)