The development is very, very slow these days, unfortunately. Nothing seems to have happened at least on GitHub after 3.8.0 beta 2 was released in 2021. I was a big fan back in the early 2000s; there are few, if any, comparable products out there, combining a high-quality, featureful renderer with an interface based on a Turing-complete scene description language rather than a graphical modeler.
It's a shame (although understandable in 1991) that the original developers chose a custom non-free "source available" license, so POV-Ray was late to the "open-source party" and the GitHub revolution due to the understandable difficulty of contacting all of the various authors and asking for re-licensing under a more popular, more permissive license, or rewriting those parts that could not be re-licensed. Back in the day (~15 years ago) the eventual goal was to release a 4.0 version which would've been a major rewrite, but I doubt that's ever going to happen.
It's a shame (although understandable in 1991) that the original developers chose a custom non-free "source available" license, so POV-Ray was late to the "open-source party" and the GitHub revolution due to the understandable difficulty of contacting all of the various authors and asking for re-licensing under a more popular, more permissive license, or rewriting those parts that could not be re-licensed. Back in the day (~15 years ago) the eventual goal was to release a 4.0 version which would've been a major rewrite, but I doubt that's ever going to happen.