The linux foundation would introduce this is an optional thing you can download, with documentation on how it works, and where you can find the source. Within 3 days the community would make self hosted servers for it.

They are not known for siphoning user data through dark patterns, so there is nothing to object from me. If they were to try it the same underhanded way as microsoft, I'd be just as much against it.

That's exactly what I would think too in this thought experiment. So Recall itself isn't the problem; it's the way Microsoft built it. I am personally still in fact waiting for a reputable organization to build it.