I think some creators pursue products as ways to fund their passions. For example, was deno deploy always the endgame or is it just a way to fund working on deno? Aside from motivation, how it's implemented and how it affects the community matters.
This part, very early on in the Bun page, stood out. That’s a monetizable product, even if the code is open source. That to me felt like positioning itself as a potential drop in replacement for Deno Deploy / Edge Functions.
There was serverless, and now the next trend is with edge computing. It’s already happening, but now specifically about runtimes on that edge.
bun isn't open source, it is source available (at this point in time, at least): https://github.com/Jarred-Sumner/bun/issues/241