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.