i'm of two minds on this:
1) if name changes were a thing when i had my first account, i couldve kept that going instead of making a new one. i wouldve been able to keep all of my history and points and whatnot and just continue onwards, sort of like how avatars arent permanent. id probably be lvl 25 like that matters at all or whatever. would also mean all badge progress would be unified, all posts and submissions and whatnot wouldve been on one page.
but... 2) i do like the idea that it's a clean slate at the same time. no past comments, no past Bad Choices, and for some it represents some sort of milestone i'd imagine. the melonadem of 2025 is certainly a different one from 2021 by a long shot but it's even a longer shot from 2014 or 2016 or 2018 or whatnot. in fact, one of the reasons i've made a m9m account back then was to try and make botb a little more Exciting because it was getting kinda grindy and mundane i suppose? i didnt know about making music for the fuck of it back then LOL so yeah
i'd say i'm in support though - having the feature for people to use would make sense, and for those who wish for a clean start can still make a new account and just not associate with the old one if they wish.
but, to say something against, it'd be technically challenging to implement i think:
1) with the current system, the id is your username, you'd maybe want to replace this with an uuid based system that randomly generates a random string of characters as an id. even so though people wld rather still have this display as barracks/profile/melonadem rather than barracks/profile/afc2-859f-32de or whatever, which would lead right back to the same problem if such a thing is implemented
2) if name changes require url changes, a lot of urls will suddenly become broken both inside and outside of botb. this isnt great naturally.
3) an username system might work best for botb - retain the same profile url, but change the display name. regardless how its implemented id argue to keep a non-public log of usernames. this can be made public by the user if they wish.
4) i'd definitely make this cost boons. i would argue having your first name change be free to fix typos, and if the name changes merely inspires what capitalization your name needs to use, then it should be a fraction of the cost if not free. i'd also slap a time limit for non-caps adjustment to be once every month, and i'd disallow renaming to existing profiles for obvious reasons.
i've had a section for potential abuse (as in, ppl registering innocuous accounts, leveling them up and then changing the nick to something recognizable that might not be as easy to spot as just making a new account witht hat name). i think a very simple solution for this particular instance is to just have admins review nickname changes. can either be a waitlist and you get approved or denied, or it happens but mods have a special view for recent name changes. either way they can take actions as needed and yeah!