If you don't abuse it, odds are good it will last longer than you will.
My oldest new model Blackhawk I bought brand new in 1983. Not sure of the round count but considering I spent most of the 80s and 90s shooting between a thousand and two thousand rounds a year recreationally, its up there.
The only thing visibly worn on my gun is the finish. And if some part does wear out, so what? You replace it and you're good for decades more, most likely.
EVERY part of every gun is replaceable except the frame/action (serial number part) and even those are legally replaceable by the manufacturer.
They are not, however, indestructible. You CAN break them, you CAN destroy them. You've got to seriously abuse the gun to do that, but it can be done, make no mistake about that.
You're going to spend several guns worth of $ on ammunition before you come close to wearing one out.