I’ve been through this dance with every band I’ve been in. In general, it seems to be that the less skilled the guitarist is, the louder they need to be. I’m sure that deteriorating hearing is part of the issue but a big challenge for at least two bands was the drummer’s volume - so loud that the guitars “had” to turn up, which made the drummer hit harder….
IEMs and a quiet stage are, in my view, the only answer. Sadly, the last guitarist I worked with didn’t see things the same way - which is mainly why I no longer gig*.
Hats off to the OP for doing what I wish I’d done many years ago.
*well, that and the fact that I’m no feckin good