How many hours did you use each device, and how many times did you recharge them (cycles)?It's not an emotional post. These are the facts:
- 16" M1 Max MacBook Pro = 100% battery health
- 13" M2 MacBook Air = 100% battery health
- 12.9 M1 iPad Pro = below 80% battery health
And the reason for this, is that Apple doesn't allow you to manage the charging behavior of the device, like what you can do on Mac.
The iPad Pro really sucks with the way it destroys batteries due to limitations Apple has put in place.
Without that information your “facts” are pointless.
In any case, even assuming that you used them all equally, batteries are consumables and eventually will need to be changed.