OLED displays now are tandem OLED displays which stack multiple layers. This means you don't need to exponentially crank up the voltage to provide more brightness which also increases lengivity of the panel (and increases battery life).
I have a, what, 2019 LG CX OLED TV. 55". Used in anger as computer monitor since new. With complete disregard for burnout. It's… perfectly fine? I can't see any dimming or patterns or faults at all.
Don't take me wrong, OLED displays on a a MacBook screen is quite a nice feat compared to regular the regular displays we have as of today.