We have one of these for our infant. https://owletcare.com/ It’s just a soft cotton good, but infants are all universally pretty small so it doesn’t need a wide range of adjustment.
OP didn’t post how long the intended wear time is. Neoprene does retain more heat, but when I suffered from carpal tunnel I wrote a neoprene wristband often 8 hours a day. Got mushy by the end of the day but not the end of the world.
Either it will look like a sock of some sort, or it will look like a house arrest bracelet. Assuming these people have mobility problems, I’m not sure how often they will be galavanting around barefoot?