Debian testing/sid is a wonderful desktop environment if you do lots of development work. I currently use stable on my laptop, as I would rather have a stable environment that sometimes needs a backport vs. a very-occasionally-unstable environment that always has the latest of everything. But for years and years I used sid as my main environment and it was extremely convenient to have always-up-to-date development everything with very little effort.

IDK, maybe it’s less of an issue now, as pyenv / npm / etc are more common and give the same type of experience. But for me back when I did it was great.