Unless the complicating factor is the "and replies" part, but are there guaranteed to be meaningful tags on replies?

Yeah, it's the "and replies" part that complicates it. Most replies don't have meaningful (or any) tags. So, I'm going to look at the root post of all comments during the interval and get tags from that. Unfortunately, it's not enough to just look for replies on all posts that were submitted during the interval because replies can be attached to posts that were submitted earlier. If I just wanted posts, it would be simple, but I want the browser extension to find everything under a tag at all depths during the interval.

I think it also creates an expectation that the solution to the lack of dev work here is to wait for an outsider to swoop in rather than trying to cultivate the social environment here to be supportive.

I suspect that the regulatory environment has been a big obstacle to development investment during the last 4 years, too. I'm hoping (🤞) that maybe we'll see more activity after January 20. We'll see.