I already limit usage very heavily. Just a few contacts left and I can remove it completely. However this is not so easy in general, as others expect to be able to reach you on FB/WhatsApp/Instagram. And even worse - almost all the social/communications companies seem to be adopting a similar stance. So there are fewer and fewer places to go.

Social connections are very important to people, and these companies are exploiting our desire to stay connected with other people - and the difficulty of changing communication platforms when there are many parties involved.

What's the alternative? You expected your high school mates to use mastodon?

Email and even SMS still do work great tho.

These don't serve the same purpose.

Stories and other things on platforms like Instagram help you stay connected with people passively without needing to find a suitable topic or a reason to start conversation of nowhere, it may make you discover a new thing to keep you connected to that person, they are interested in something you are curious about, thinking of traveling to the same place, etc.

You feel connected to people by looking at their pictures and avoid talking to them? Honestly not sure why I would want to feel connected to anyone I don't have a reason to talk to

Connected was probably the wrong word, more like up to date.

since i dont use that, no. I would however expect sms or email to work, maybe telegram, maybe signal. and if they cannot "inconvenience" themselves slightly for that, I dont quite think I need them

Expect*

Well they are functional monopolies but also even if you don't use Meta services, if any of your friends posted a photo with you on there, it can also be used for training and without an account, you can't even object to that.