This is a good perspective. I did work in lisp, including production systems (albeit small systems), for many years and authored many open source projects in CL. I'd say the biggest hurdle was the community. There was a strange balance between getting contributors and people going off and rewriting the thing you're working on becuase they can do it better/make it faster/etc. It definitely skews towards people going lone-wolf. A lot of people said this going in but I ignored it because I love the language (still do) but eventually got burned out on trying to do anything real with CL. I absolutely did get highly impactful contributors on some of my projects, and I'm still thankful to them, but there was also some "this isn't fast enough I'm going to just rewrite it" that frustrated me a lot.

One place I think CL absolutely would shine is game dev. I started using it for that a bit and the ability to redefine the system while it's running is an incredible superpower. Forget compile times, rebuilding the state of a game can take a long time and being able to fix a bug or adjust behavior right then and there is really cool. This probably isn't even novel anymore given modern game engines, but at the time I loved it.