Why can’t people just accept that their memory isn’t perfect?
I’m not really saying I actually believe in an alternate universe but there is a significant number of people who claim they remember it as Stein. There’s even groups dedicated to trying to prove it lol
My totally unqualified explanation is that ‘stein’ is a more common suffix than ‘stain’, so a lot of people (me included) just assumed it was ‘stein’ without looking closely.