Chain drops are off topic, but I blame the chain rings. I've used Force AXS for over 3 years and never had a chain drop, but I've only used Campy 48/32 and Shimano grx 48/31 and 46/30 cranks. I've owned 7 grx cranks and 2 Campy 12 cranks. All were easy to set up. The flat top chain worked great with both Campy 12 and grx 11 speed cranks. I recently bought a matched pair of 44/28 chain rings for grx cranks from Specialties TA. They shifted poorly. The best I could do with the shift to the big was get it to work when the chain was on one of the 4 largest sprockets when the shift was made. Otherwise, the chain dropped to the outside every time. I took them off, put the grx rings back on immediately got my perfect shifting back.
Also off topic are complaints about chain ring sizes. Apparently some users don't understand that a 48/10 is like a 53/11 and a 46/10 is like a 50/11. What I don't like is the limited range of the cranks. I want a 16T difference, not 13T.
The 29mm crank spindle shouldn't be a problem. Sram BBs use standard 30mm bearings, but with a thin plastic bushing that at least attempts to avoid the spindle ruining wear that often occurs with an aluminum axle and hard steel bearing. I like my 24mm Shimano spindles with wheels manufacturing thread together BBs that have angular contact bearings. Setting the bearing preload is much easier.