As someone who's new to the fediverse, can you (or others) explain a bit more about how the costs of an instance might affect us? I was pondering this a bit yesterday; at the end of the day, hosting an interactive site at scale can get very expensive.

Specifically:

• how does the fediverse model address costs at scale?
• what happens if an instance closes? How does that affect content hosted there, as well as user accounts registered there?
• I figured joining a large instance would be the best thing to do (more content and engagement), but now I'm wondering if that's at all true. Maybe a smaller instance is less likely to grow so much that costs are a problem, and the fediverse model itself provides the cross instance content?