Honest question... does the multi account player not still have advantage there? Maybe even more so?
With 1 account I would get 1 free attempt, then 1 cheap attempt, then 1 more expensive etc. to try again and hope for better rules that allow for a higher score.
With 2+ accounts I would have 2+ free attempts. I would also have 2+ cheap attempts, 2+ more expensive etc. The more accounts one has the more attempts at favorable rules they have and chances at cheaply placing well for that day.
If rules were set per day, a player with multi accounts would still have more chances at better rules for the day since 1 of the accounts will have more favorable rules than the others, but they would also be stuck with some accounts with horrible rules for the day. Would this not be more fair to those who do not have multi-accounts or tons of DEC to spend since statistically everyone should then have days where they have good rules and days with not so good ones?
Edit to add: For the record I'm down for some type of KYC system with limits on both how many accounts a player can have and restricting things so multi-accounts can not be in the same league. Imo anything else is just Band-Aid fixes.