socially, mtf is probably worse. people see them as degenerate coomer fetishists at best, or as dangerous sexual predators at worst, and with good reason.
ftm get a lot more benefit of the doubt due to being harmless.
but physically i think ftm is way worse because the irreversible damage from hormones is much more brutal in them.
for an mtf, detransitioning is pretty easy - have the titty implants taken out, take off the wig, dress normally, and he immediately passes as a man again. a slightly ugly man probably, but will still be gendered correctly by everybody. at worst he'll be left with man boobs (gynaecomastia from estrogen pills) but plenty of regular fat dudes have these as well so people will still correctly gender him as a man.
and if he didn't have them removed, then his dick and balls will start working normally again after he's off hormone pills for a while. might need some TRT but he'll go back to being a fully functional man eventually.
for an ftm on the other hand detransitioning is difficult. stopping the testosterone injections won't make the pube beard go away, and it won't make her voice go back to normal high pitch woman voice either. also, all the testosterone can leave her permanently infertile, even if she didn't have any surgeries.