This is the specific area of db_errors that I work on-- error #902. I focus specifically on the subset that are orphaned profiles where there is no PM, no data in the fields and no connection to another profile.
I do an initial scan to see if I can find any facts about the person. Sometimes there are clues in the narrative. The privacy tab reveals if anyone is on the Trusted List. The changes log will reveal who created the profile. If either are still active on wikitree, I post a comment in the appropriate places and hope for action. (90% of the time there is either no response or the response is some variation of "do whatever you want with it...").
Only then will I "merge away" the profile. I search the surname list for another profile with the same name and NO profile manager (but one with data and connections) and merge with that one.
Failing that, I find a willing PM who will support a merge but be careful with this last. If the PM doesn't fully understand what you're trying to do, the data of the "solid" profile might get messed up. That's why I prefer merging away into an orphaned profile.