I've had three Pis running more or less continuously off a microSD for a few years, and none of those cards (same as original) have gotten corrupted. These aren't running zillions of writers per day or anything, but most people's problems stem more from bad power supplies or cheap cards than the Pi's use of microSD itself.
You should probably run iostat in your tests too, to have high bandwidth is completely useless if it has high latency. Just like a high framrate game is unplayable if the frames are instead delayed so the motion to photon delay is many frames.
Companies are now cheating in every way they can to extend and pretend, and now as the peak density on the flash media reveals that they break with time it's going to get messy!
I've had three Pis running more or less continuously off a microSD for a few years, and none of those cards (same as original) have gotten corrupted. These aren't running zillions of writers per day or anything, but most people's problems stem more from bad power supplies or cheap cards than the Pi's use of microSD itself.