New comment on reddit

Pros: less to manage

Cons: you may end up with a lot of zombie accounts if folks keep creating new ones

IMO, the best way to handle this is to deactivate after some threshold (for eBay it might be ”never”…for CNN’s comment section, it might be weeks), and delete after another cut-off – its how most businesses I've ever seen handle retiring former employee accounts: they deactivate within hours of their final employment time, and delete after 30-90 days (depending on regulatory requirements)

The university I graduated from did something of a hybrid – if you had ever applied or attended or worked there, you were given a ”username” in their HR/student system. And no one else would ever get that ID. But in Active Directory, only current faculty/staff/students had accounts – and those were managed based on whether they were active at the school or not