No idea. The non-working ones were made by the PT (old group) and the idiots tied them to specific mod files in official rooms. OFC those mods were horribly broken and got replaced with better working ones. The achievements weren't though.

Achievements are for people to look at, and how good you are. For example, the "Sensei" achievement means that you have achieved a rank of 500.
But it isn't serious in any way.
Also I really don't think the broken achievements make sense at all.
Kind of like that B.I.T.C.H achievement.
There are only 9 players who have got it...

BITCH is once again a PT one, and had to be handed out manually. Nothing more than a joke achievement cept without the joke.

The rank ones are a whole other story. Some date back to a ye olde ranking system, when your rank didn't change every time you fart & getting to global #500+ would take effort instead of just rank farming some shitty broken mod.
When rank was changed to per belt they still worked, since then the change has pretty much killed them.

TBH with the current system achievements for it would be pointless. It takes no effort at all to fire yourself up to the top of the rankings if you want, and if someone coughs in your general direction you'll drop back down again.

I may as well get the event specific achievements out the way while I'm at it - simply put if you weren't in it, didn't win it & don't have some form of time machine then you aint gonna get them all.