How to choose between 10 speed vs 12 speed drivetrain on mountain bike. Pros and Cons
It comes down to what you would enjoy more - how you prefer to ride vs cost.

I can't find any durability tests I trust but from my reading the general impression I get is that 10 speeds is no more or less durable than 12.

You have ridden many different drivetrains so you have built up experience that should guide your preference. 2 extra speeds in the shifting range is nice, is it nice enough to justify the cost? Only you can make that call.