I agree with everything you said, although I do think it applies much more towards jazz and classical rather than pop music. Making satisfying music by yourself on the guitar is definitely difficult, especially if you don't sing.

However, playing johnny ramone style 3 chord punk in a band is, as you know, just not that difficult. So, I think it's not just the inherent complexity of the instrument, but also the context you are trying to make music in.