(I don’t use proprietary GitHub things like “bots” and “pull requests”, so I’ll just talk about the “conventional commits” stuff in general)
I like the idea of standardising “unimportant” things like commit message format, since it’s one less thing to I have to think about right now, but may help me out in the future. Tooling is the best way to standardise these things, since following the standard becomes the path of least resistance (compared to, e.g. forcibly skipping git hooks).
One thing I don’t see from clicking around the links is how I’d run this “commitizen” stuff from Magit; the use of an interactive CLI (rather than, say, stdio, env vars or arguments) makes me think it would be tricky.
Incidentally, I was thinking earlier today how I’m terrible at keeping changelogs and if there’s a simple way to enforce it. This would do the job nicely!