For every negative review, there's a positive one...
I've been running with AirPods pro for a year now, averaging about 180 miles a month, including a couple of half marathon races. They are easily the best headphones I've used for running. They sound fantastic, the transparency mode allows me to enjoy music while hearing everything around me. And they stay in my ears without any issues. Yesterday I ran 14 miles and didn't have to touch/adjust my AirPods in my ears once.
Everyone's ears are slightly different. They fit mine perfectly and stay put. Sorry they didn't work out for you, but I thought I'd share my story for any readers who are considering these for their own workouts. Give them a try, they might fail you, or you might be like me and find them the best headphones you've ever used for running.