Yes, they will always grow back unless the follicles are damaged, or the chook gets so old the follicles fail, or the chook has genetics causing unusually early failure or retardation of regrowth cycles. Some follicles have inbuilt cycles of regrowth which are limited to a specific number.
I'd recommend getting rid of the rooster, personally, but that's obviously a very personal choice.
I don't believe 'overmating' exists, since I've run ratios of up to 50:50 males and females all together in a flock numbering over 100 on average, for years, and 'overmating' has never occurred, whereas others have run male-female ratios of up to 1:100, with 'overmating' occurring despite most of those hens never even getting mated. The key difference is that only rough males cause overmating and it's got everything to do with how rough he is and nothing to do with how often he mates. A rooster who isn't rough can mate 50 times a day and he won't cause 'overmating', ever. A rooster who's rough can mate 3 times a day and cause severe 'overmating' progressively and rapidly. So-called 'overmating' is the term incorrectly used for a rooster who habitually destroys feathers. It's got nothing to do with mating, it's not even a normal or necessary part of the process!
I select against rough and violent animals and don't have 'overmating', those who don't select against rough/violent animals do have 'overmating' --- and my hens are often far more sexually active than the average 'overmated hens'. On this note an all female flock can also be 'overmated'... Feather picking by any other name, lol. We treat it in hens but accept it in roosters. Well, I don't, anyway...
It's utterly unnecessary for a male to damage the female while mating, and it's very heritable. For my hens' sakes I only keep males who don't make their lives a regularly painful misery. Saddles may be an interim answer for some but I also don't believe in altering a hen's normal habits i.e. dustbathing and preening by putting something on her just to protect her from a superfluous male's attacks. However I know this isn't an option for many, to just cull a nasty or callous male, so whatever your choices, I hope it works out for you.
Best wishes.