The prolog community is pretty active. SWI has a discourse group. There's SWISH, CLP(FD/Z), abduction via CHR (a rewrite system) or libraries like ACLP. Prolog is homoiconic, and it achieves it in a unique way, via things like functor/3 and =../2 rather than a macro system. There's growing interest in ISO-standard, pure, monotonic prolog for writing large, clean prolog codebases. SWI is the most mature prolog, but Scryer and Trealla are very active and ISO conformant. Trealla is quite embeddable, particularly in javascript codebases. There's also janus for python, and the community is looking to integrate prolog with LLMs.
Prolog shines for writing bidirectional parsers, NLP, expert systems, abductive reasoning, and constraint logic programming. Pure monotonic prolog has some very useful properties in terms of debuggability, making it useful for large prolog programs. There's also some interesting work in developing pure io (library(pio)). Prolog also has a few different techniques for coroutining, including shift/reset. Markus Triska has a very nice youtube series and book on prolog that's worth watching/reading.
The main downside to prolog is really just that there's a steep learning curve to it that puts a lot of people off and prevents it from gaining more traction, similar to why langs like lisp, haskell, and idris have trouble gaining traction. SWI has a lot of features, but it's also not ISO conformant, and a lot of libraries aren't portable and/or feel very procedural/imperative, which defeats the purpose of prolog. The useful libraries can often be ported to less popular prologs that are more promising, like scryer and trealla. For example, I managed to port ACLP to trealla yesterday without much effort, which is a pretty useful abductive system for writing expert systems or any sort of abductive reasoning.