I agree in most part but the ball bearings in motors will definitely not last for 10s of thousands of hours. When I was flying the DJI hexa Flywheel many years ago bearings in those motors were the weak point and needed to be replaced quite...
I mean nothing lasts forever, right?
What periodic maintenance would you recommend to do to keep the M3P in good nick and airworthy? Like changing props after x number of flight hours, even if they are looking perfectly fine and undamaged ? Or...
There is always a trade off. Bigger sensors mean bigger gimbal and bigger gimbal means bigger drone. With that comes bigger battery to maintain a decent flight time etc etc. The M3P is, at least IMHO already a great example of optimal balance...
Bigger sensors require bigger (and heavier) lenses and bigger, stronger gimbals.
Looking at the camera module on the Mavic 4, or the size of the X7 lenses, you can see that there won't be a bigger sensor.