One thing I've noticed that's interesting about eBay is how they want to skirt any responsibility for dealing with troublesome members outside of transactions.
Years ago I got an email from someone I bought from and had a dispute with because he forgot to include something, and he threated me with physical violence. eBay just didn't give a shit and said it wasn't their problem despite the written proof. I realize if I really felt threatened, I could go to the police, as that's what they're for. This particularly challenged individual was across the country, so I was a bit alarmed but guessed the odds of him actually carrying out his threat were low. But eBay would rather force people to complain to law enforcement than invest the time or energy into disciplining or banning its own troublesome members. There was proof this idiot sent me a threat, but eBay is more than content to allow him to continue to spend money on their website, because at the end of the day, the almighty dollar speaks loudest.
I recently got an email from another idiot who I had previously declined a "Best Offer" from (and I didn't even outright decline it, I just let it expire), bragging to me he got the item in better condition and for a cheaper price, so I should enjoy never being able to sell my item. Obviously the idiot went right on the blocked buyer's list. But out of curiosity I wanted to see if there was a way to report him, because the message at that point was genuinely not about the item in question anymore - it's sole purpose was to harass and try to inflame me. It was spam. eBay's rules/policy states you: "Can't use our member-to-member contact options to send spam or threats." In reality, it was a minor annoyance the way I perceived it. But shit stains like that are obviously going to be trouble at some point for other users and in other transactions. If I can just click a button and possibly get this idiot's account flagged, hey, why not?
But alas, eBay has no way to report them. They literally just say "Sometimes another eBay user's behavior and communications are out of line with eBay community practices, yet not against eBay policy. Even if the actions are in violation of eBay policies, we aren't always able to investigate policy violations. Consider working with another eBay user." Well no shit eBay. Of course I'm going to work with another user. And of course you don't care if policies are violated as long as people are still buying and selling and you're making money.
Obviously the best course of action is just to ignore the idiots, but I felt compelled to kindly tell this person I was concerned for his mental health since he took an eBay Best Offer expiration so personally, so he should look into mental health resources online and that I hope he gets the help he needs. Although I guess it would be interesting if my response made the guy think "Yeah, what was I thinking? Why am I so empty and unhappy inside that I felt the need to send that first email? Maybe I should talk to someone."