I joined my first rock band when I was 13, in 1968.
I knew nothing but had been playing/studying with teachers for 6-7 years so
it was simply more learning.
For the next 18 years up until I quit playing guitar in '86 it was still about learning.
The problem or issues was that having to deal with other people I was learning
more about them than how to make music with them.
Needless to say but people can teach you a lot of things you really don't want to know.
I found life and music was much better without them.
The cool thing is that the internet changed all of that. Computers are very easy to turn off
and it brought playing guitar back into my life although it hasn't replaced the energy that
is made by musicians playing together.
IMO the thing that I learned most about being in a band is about how to be a good
musician to work with and create music with other musicians.
The cool thing is that one learns many different things because the band isn't always
on the stage.
One learns from the practice sessions, the studio work, the jams, etc...if they're paying attention. I learned that many musicians have trouble with that part. :)
Oh...thought I should add...I know that I looked the same to all of them at one time or another as they looked to me. Part of learning I think.