I decided a few years ago that Signal was the closest thing to a good cross-platform messaging client that mortals could be expected to use. I sent an email to my most frequently texted contacts asking them to consider installing it and using it.
It’s not a huge cross-section of my friends and family that uses it, but I message a portion of my social network graph every day.
$5/month for a communication app, that is in essence a daily driver, is reasonable for most European/North America users.
Having said that, no-one in my circle uses Signal :/