[tommydoesntknow]

I don't. I read them, act on them, then delete them. If I think I might need it later, I take a screenshot. How often do I miss deleting SMS messages? Maybe once or twice in 30 years. That SMS came from somewhere, so if it's really important, I can go to the source.

I use email the same basic way, pruning almost every message weekly on Sunday.

Sunday is also Stop Subscription Sunday, like Taco Tuesday, but for software and app rent-seekers.