Depends on what you ride. I used to alternate between SPDs and flats as being clipped in can promote bad technique, especially for jumps. But these days I ride flats all the time. Just prefer not being connected to the bike when riding steeps, as crashing is a certainty.
I'll be fitting some flats after Torq, for this very reason. Want to learn how to bunny hop properly, and get out of the habit of pulling up on the pedals.
Is it a mistake to have SPDs on mtb?
wondering about the pros and cons of clipless vs platforms