most of the local bars and restaurants had egomaniacal DJs who think louder is better

I was referring specifically to the problem of loudness - and some local places on this night. However I think the problem of loudness is widespread, amongst DJs - in my limited experience - but also in live concerts and music in pubs - hence the general increase in hearing damage in recent decades as reported by the BBC.

Maybe it's because I'm a Londoner - that I moved to Nice.