Exactly. No one pays for it because it’s free

Check out Circles

It will. I did the same thing a couple years ago. Make sure you share links to things like articles, videos, news, from the fediverse to your contacts. That helps them switch, when they see the platform in their mobile browser.

SMS is generally free and unlimited with almost any postpaid mobile plan. If you’re still paying for SMS then you should switch providers.

It has to start with someone. I made my entire family switch to signal by boycotting WhatsApp. I just said, of you want to contact me your can either SMS, email or install signal. It was surprisingly easy. For non family members, I tell people to switch all the time. Most of my contacts now use signal. It was worth the trouble.

You still pay for SMS? Wtf, what country do you live in? Most postpaid mobile plans these days only charge for data usage. In which case, your still paying to use WhatsApp.

There benefit would be exactly what this top comment is about. For all those people in your contacts who don’t use signal, you could still use signal to message them, it would just be an SMS message. It would therefore also become more enticing for people to switch from their stock SMS app to signal, because it would make no difference in terms of who you can send SMS messages to. It would allow for the signal user base to grow, solving the issue of “no one uses signal”