Has anybody had any success with a post-only approach to social media? Or is the temptation to check the timeline too strong?

Same. Quit over a year ago. I find that nothing of value has been lost. If something is really important, people around you will let you know.

Quit 8 years ago. Had two attempts to get back - one around 4 years ago when i just got bored out of it in a couple days, and one around 3 months ago when i was horrified to see the streams of extreme right, black pill, porn, scam, "fun history facts and news of tech" content - all made up or horrendously exaggerated for clickbait in a trivial-to-verify way...