Facebook I left a decade ago, for its ethical issues. Instagram I left because I felt the performance aspect was unhealthy: even in my only-friends-and-family circle, I'd still care too much about picking out the perfect photo of my kid or wherever.

For Twitter I realized it was way too easy to get sucked down political/angry feeds. One day Twitter said my account has suspicious activity (maybe a bot tried to log in) and I needed to reply to an email to re-enable it. I never replied to the email. Somehow this meant that every time I followed a Twitter link, I'd get that alert, so I could never see content. I felt so much happier.