This is an issue for me too. I know the meme is "your real friends will still make the effort and call you / hang out with you / whatever", but I don't think it's that simple— we (especially in the pandemic, but really always) rely on social gatherings/media as a proving ground for acquaintanceships, a place to banter back and forth and onramp a relationship to the point where it would be not-weird to actually arrange an intentional activity or get-together.
And the reality is, when I've had acquaintances fall off my social media radar or be otherwise difficult to get ahold of, I just can't be bothered. When every person but one is in a FB Messenger group chat, and one person wants to be texted-with about what the plans are, that person inevitably gets left behind.
So maybe there's some FOMO going on here, but I don't think I'm at a place in my mid-thirties where I'm ready to effectively shut the door on those opportunities.
Plus I don't find social media AT ALL toxic and I only spend maybe a half hour a week total on it. OTOH I find people complaining about social media being toxic is becoming extremely toxic.
There used to be nice dumb phones with physical qwerty keyboards. They were wonderful for texting. It's a real shame they're not made anymore.
A couple other things I've thought about, more on the social media angle, are (1) starting a personal web site again, and (2) a different kind of social media site. For (1), I've already got a little VM that runs my email and some quickie web apps I threw together. Why not stand up a personal site too, like a lot of us used to have, where I can share all the stuff I'd normally be putting on Instagram, etc.? Obviously that's adding friction for folks too, but I'm less concerned about that stuff getting ignored.
For (2), and bear with me because this is going to sound a bit woo-woo, I think a social gratitude list could be really powerful. Maybe not a big hit, but definitely powerful for people who would use it. I say this because I used to be on an email list with some friends where everyone would write ten things they were grateful for that day and then send it to the list. Now, if this is not a practice you're comfortable with, you're probably dry-heaving right now; I did too at first. But once I got past the fact that it's not very cool, I found that it was a fantastic way to keep up with folks. (That's in addition to the mental health benefits, which I think are evidence-based but I'd have to double-check that to be sure.) Amazingly, I didn't even notice a tendency for it to degrade into performativity or attention-seeking. Overall I just think it would be a structure that would enable some of the positive aspects of social media while discouraging or eliminating the negatives.