The benefit to me is that snaps update as soon as the patch is pushed and they sandbox better than flatpak. Its also easier to maintain a snap from a dev perspective (idk if thats true I just read it on some fourm)

I prefer flatpak because i like the name and flathub better but the development has kind of stagnated and a lot of their benefits are non existent. Flatpak sandbox is kind of a meme at the moment because most apps ask for way to many perms just to work.