I think everyone can agree that cover-based combat, done right, is just fine. You run into problems when devs get lazy. Environments littered with convenient, artificial cover really break immersion. Enemies with truckloads of health turn gunfights into unsatisfying, overlong games of whack-a-mole. Regenerating health takes most of the risk (and thrill) out of combat.
Cover needs to be highly organic with respect to the environment. Enemies should drop quickly and violently when exposed. Players, too. That's how you craft convincing, tense, exciting gunplay. That's also usually not how it goes.
Much as I enjoy a challenge, I never play the Gears games on anything higher than medium difficulty. It's not that I can't handle it. I can't handle how bored I get pumping an entire magazine into one guy's head before he finally goes down.