Sony still makes very nice players - under the "walkman" brand no less. https://electronics.sony.com/audio/walkman-digital-recorders... . Probably too pricey for a 10-y-old child, but you might be able to find a used one on ebay?

This are just dumbed down phones in a sense: I don't want my mp3 player to be running android. I want a minimal piece of software that lets me quickly navigate to the songs that I want, and physical buttons to do it. I've look long and hard for something like this and cannot for the life of me find it. I'm really sad that I lost my Ipod classic 10 years ago.