There are several people on this forum who have said, in previous threads, that they don't care for jazz - a fair comment. I would say, having played jazz in various forms for many, many years, that being part of a jazz outfit - duo, trio or full band - is excellent training for the guitar.

For years I rarely played an "open" chord, with main keys being Bb, Eb, F, etc. - a good discipline. And learned to transpose instantly, i.e. play in any key. In sessions, when joining in with other people who use capos, I try and avoid the capo, and play in their key on the open fretboard - or shut up if too difficult!