Indeed, and reading through the thread, there's an optional rule to apply a fail state on a roll of 1.
Not in 5e rules there's not. Source? Citation?
Also, Halfling luck has not been implemented at all and doesn't happen in game, despite it being listed on your character sheet.
it's just a regression, it worked fine on the previous patch
I've had it officially confirmed that it simply has not been implemented at all, as of yet, so if you thought it was working before, that was human error, I'm afraid... Or else one department in Larian doesn't know what the other is doing.