It's like being in a relationship and breaking up because one is unhappy but refusing to talk to the other person about it. If you're unhappy with your pay and that's the only reason you're thinking about quitting, bring it up, what's the worst that could happen? To the people that say "retaliation", I find that highly unlikely. Every single place I've worked at, at least tried to accommodate me.
It's more like: you realize your SO for the past year has been putting in the bare minimum effort into the relationship and decide it's not even worth the conversation.
Missed opportunity really. That's a year of not having a conversation about something that's bothering you. Sure people can live their lives however they want, but talking about issues, for me, on average resulted in better outcomes than not talking. That applies to romantic relationships as well as professional ones.
Somehow people seem to think it has to be one sided when it comes to professional relationships with your employer. Maybe it's a lack of structured, routine, two sided feedback that makes people not bring up issues around compensation. Maybe employers should ask proactively if the employee is happy with their compensation.
