Was starting to think about setting up a neighborhood Signal group, but now thinking that maybe something like Briar might be safer... only problem is that Briar only works on Android which is going to exclude a lot of iPhone users.
I live in NY now. Just today, I got a message from a close friend who also did SF->NY "I'm deleting Signal to get more space on my phone, because nobody here uses it. Find me on WhatsApp or SMS."
To a naïve audience, Signal can have a stigma "I don't do anything illegal, so why should I bother maintaining yet-another messenger whose core competency is private messaging?" Signal is reasonably mainstream, and there are still a lot of people who won't use it.
I suspect you'll have an uphill battle using something even more obscure.
Aside: I see similar attitudes when I mention I use VPN all of the time