You don't use an IM service, because a subset of its users are "wackos"? I've used Telegram for many years now, and aside from the occasional "hot singles in your area" type spam, I've never been bothered by anyone.
The actual reason why I use an IM is the HOA, as I said. Else I do not have and do not need an IM, except for my ejabberd server + Conversations clients so that devices can send me status updates, like "backup completed successfully".
It's the only IM I have used that works most of the time, is not Google or Meta, is free and is easy enough to get working for normies.
I'd use IRC, XMPP or Matrix but then I cannot contact the non-tech friends I want to chat with from time to time.
And even then, if the spammer buys premium, they can still message you!
Sadly there are too many data leaks so those phone numbers are out there.
The spam messages I receive don't address me by name. They're generic.