I have ridden with spds since 92 I think, and realize I've only ever toured with spds except for a few trips at the beginning, 89,90, 91.
Over the last bunch of years i have been riding flats commuting , winter commuting and fat biking in winter so have gotten used to them, and they work fine.
I do really like on rough stuff how being clipped in has it's advantages being bounced all over the place, but could see using flats bikepacking where one has to very frequently take a foot off a pedal on sketchy trails, single track.
But hey, I figure it's all good and can see the pluses of both.
I've actually found that it's faster to get a foot off a clipless pedal than from a spiked flat pedal. I went fatbiking today and again had multiple instances where my front tire washed out or dropped off the hard pack into softer snow and every time my foot just shot off from the pedal saving my proverbial (and literal) backside.
The ride before that I had a defective left pedal so occasionally my foot would stick for a fraction of a second or so. My left side is blue and black from that ride. It's weird how little powder snow does to cushion roots and rocks. First time ever I needed my back armour too.