My friends on Signal do, but I have no idea how widespread it is across their whole userbase. It's not as in-your-face as Instagram, which is actually kind of nice, but like it's being said - signal is social media. you can choose to not use that feature but that's on you. To look at you and your friend group and extrapolate from there is not science, or data driven. the plural of anecdote is not data.
It's like saying no one uses Facebook or Google anymore. That's true for certain bubbles, and it's hard to know when you're in one, but, say least for those two,
it's not too hard to look outside your bubble.
Now the cryptocurrency integration, that one I do wonder about. (Since my friend group doesn't use it and I'm extrapolating :) ).
