It used to be the case than condenser mics tended to get weak after a lot of use. Not sure if that is true today. Anyway, the question was about dynamic mics.
Having said this though, I have a couple of EV bicentennial commemorative mics that I bought in 1976. One has my name engraved on it (it was a special offer back then). They are condensers and last time I tried one, it still sounded the same to me.
I'll bet my hearing has deteriorated more than any of the mics.
DonM