I started to have the same issue about 10 years ago. Suddenly bars and crowded places became far less enjoyable for me because I had such a hard time keeping up with conversations. I had my hearing checked and while it wasn't perfect, it was just normal for my age.

I remember reading that it had to do with how I processed language and sounds, and that there was no real cure yet as a few years ago.

The last couple years has made it far less of a problem but as we start to return to normal (eventually) I'd love to figure it out. I tend to feel bad sitting through a conversation where I'm only hearing about a third of what others are saying.