“Fit/strong enough”
or
“bad at adjusting front mechs”
That said I go through a cassette about once a year, so an ultra trendy 1×12 just wouldn’t make financial sense given how eye wateringly expensive they are.
I don’t really know why, but I find 1x cassettes wear slower. Not just posh SRAM super-cassettes, even my expanded XT setups on the other bikes outlive a normal XT cassette by a good chunk. The only thing i can think of is that the mud clearing is massively better, it spares them a lot of grinding… But it’s a bigger difference than I’d expect from that really, that doesn’t feel like the right explanation.
With my 1×11 SRAM, it’s miles better than any previous cassette I’ve used, in the same use it’s lasted about twice as long as I’d expect from XT. So I think it’ll work out not actually much more expensive. Admittedly I’m paranoid about maintenance!