I'm posting this following the discussion at Should we disallow users from immediately deleting their accounts if they've made one post?, which seems to be positive and generally in favor of doing this. I got reminded of this issue again because the same thing I mentioned in the other post happened just now, and I figured I should file a formal request for this.
Some facts for context:
Currently, any user can request that their account be deleted, by going to the relevant page in their profile settings and clicking the button. For users who've made 0-1 posts (and haven't voted more than once), their account is immediately deleted. For others, it starts a 24-hour timer ticking towards deletion, which can be cancelled by the user.
Additionally, if an account with an active suspension is deleted (suspended users can still delete their accounts; the link doesn't show in their profile settings, but they can still access the page manually), the suspension is reinstated on any new accounts they create, as part of the Anti-Recidivism System.
Finally, if a moderator deletes or destroys an account for spam or abuse, a 14-day "suspension" is recorded under the account immediately before the account is deleted. This "suspension" is "reinstated" if the same user creates another account.
These days, we've been encountering a troll (full details only visible to members of the Charcoal Team on Stack Overflow Teams) who seems to know all of the above facts and immediately deletes their account after making their trollish post. This allows them to sidestep the Anti-Recidivism System, as it's usually too early for a moderator to arrive and suspend their account, or delete it for abuse, and they effectively get out without any sort of block.
Also, I believe that the reason behind allowing users to delete their accounts immediately if they've posted once is historical: this feature was introduced before there was any sort of 24-hour timer, and all deletions were otherwise handled manually by SE staff. This would allow users to leave the site gracefully if they tested the waters and decided they didn't like it. However, it doesn't make much sense anymore, since users can now start the 24-hour deletion timer by themselves, immediately.
There were other solutions proposed in the discussion post I linked, such as to allow moderators to take actions like issue suspensions on deleted accounts, or to "soft-delete" accounts instead of the current model of hard-deleting them, but I'm sticking to my original proposed solution because according to Shog, this is the most technically feasible solution.
In summary, the system should be changed to only immediately delete accounts if the user has made 0 posts, instead of deleting immediately if the user has made 0-1 posts. Users who've made one post should have to wait 24 hours like everyone else. This way, we can prevent trolls from getting away scot-free by allowing them to delete their account to avoid suspension.