The removal was a panic decision to cater to a certain crowd. WotC has a history of overreaction and throwing the baby out with the bath water. They didn't need to completely remove alignment when including it as a clearly optional rule would have been more than sufficient.
Or its the realisation the rule hasn't been doing anything and, given how stripped back it was earlier, wasn't too hard to take away the last few vestages of it.
If alignment was the be-all end-all they wouldn't have stripped it as far back as they did with no effect.
I will not accept the reason for removal to be “we fear it may be harmful for others” and will treat that particular reason with the absolute contempt it deserves.
Its a clunky hot mess of a rule who's only purpose in the game is to cause rule arguments, screw various class combos over, provide a consistent source of r/rpghorrorstories tales, and make me really angry at Dragonlance. Its a rule that causes a worse game whenever it raises its head because it only ever pops up in the situations of "I arbiterily think you're not roleplaying the way I think you should be" or "My character does something to affect the party and ruin the game because their alignment declares they must".
Alignment is not a good rule at its core. Its benefits to the game are narratively and, even then, limited as "This guy is a bit of a jerk" does the same thing with less moral quandries. It does not enrich the game by its presence, as the cases where it appears have tended to be directly countering someone doing something. Its an old, messy thing from its wargaming roots, but with most of its modern use being a bludgeon to punish players with. The cases it pops up cause so much strife and drama we've been meming about it for absolute decades. Heck, you can find old alignment posting back in Dragon of all places. Sometimes you just have to look at a rule, go 'this causes more problems than its solves', and finally excise the mess.
oh and while it is valid that labelling entire races with the brush isn't a good look at any time, if I'm going to stab into any of that then I'm going to stab into Dragonlance having the audacity to call any of its elf races as 'good' in any way, shape or form but, Mecheon hates Dragonlance is a longrunning thing