What qualifies as a dead artist url?

I've been trying to clean up links from some artists referencing old accounts, blogs, websites, etc that no longer exist. That's mostly been fine, but occasionally I run into discrepancies.

Is an account with removed or no posts or activity supposed to be kept active? Or is it safe to remove the link if it's likely an incorrect account?
I set the Twitter/X account urls for artist #64509 as dead as the account has no posts or followers. Honestly, I think it may have been added initially as a mistake or typo, but I set it to inactive to be safe. I can't find any account history for it, the active pixiv account doesn't reference it, and no posts credited to the artist on Danbooru or other boorus even cite a twitter link. Despite that, it keeps getting set back to active.

Conversely, in the past I found a few urls on different artists flagged as dead just because there were no new posts, but the account or page is still full of accessible artwork even if it's unused. (ie, a pixiv account unused in 5 years with 100+ posts) Do those links count as dead, or should those be set back to active?

My belief is that URLs should only be marked as dead if they're completely inaccessible, not just empty or inactive.

URLs are dead if they are inaccessible. Many artists regularly delete some or all of ther posts, but their accounts being empty afterwards doesn't mean they're dead. They might post again, and either way it's still in their possession. In a case like artist #64509 you'd either have to leave it as active (because it is) or find a way to verify that it isn't actually the artist. That last option seems unlikely after 14 years, so it's best to leave it be (not like it hurts anyone or anything anyway).

URLs that are alive being marked as dead just sounds like a mistake. It's still mostly a manual process, and sometimes websites being down temporarily also lead to people mistakenly marking URLs as dead (the bot editing artist #64509 has also suffered from this on occasion).

In general I'd say "it'd dead when it's dead". Don't try to overthink it, just see if the page works (alive) or if it gives a 404 or something similar (dead).

So links to existing accounts or websites flagged as dead should be set back to live?
And empty or inactive (but still accessible) accounts should also be considered live?

jlyker89 said in forum #441827:

So links to existing accounts or websites flagged as dead should be set back to live?
And empty or inactive (but still accessible) accounts should also be considered live?

Yes, just be careful for sites that allow reuse of handles, specifically Twitter. A Twitter account could be dead but someone else made a new account under the same handle, it will have a different user ID though.