I don't think I experienced this when I was younger, but, now, it feels like being "on" (e.g., on Discord, even if it's closed and sitting in the tray and I'm getting no messages) incurs some subconscious stress somehow.

I'm not getting any messages, but I could get some at any moment. And then I'd have to choose whether to respond immediately or not. And, while I'm not responding, some part of me is wondering what the message's level of urgency is.

It sucks. Exiting Discord entirely for some portion of the day when I don't feel up to being "on" literally feels like going on vacation without your phone or something. My brain can finally relax. https://youtu.be/E2-AnDdgIF4?t=17

you can mute specific servers and channels. I use this judiciously

Consider the recent studies that show that people's attention is reduced by their phone, even if its under their bed, even if its turned off.

Try it, purposefully leave your phone at home the next time you go to the grocery store and see if you feel anything weird.

I would never bring my phone to the grocery store. It feels good leaving in a place to get recharged where it can't be lost.

You can disable notifications entirely

This is like idling on IRC.