D&D is the most famous tabletop RPG yes. There's a large variety in them though, so calling them all D&D games would be like calling all sports Football. Of these games it looks like Dead After Dinner, Desperation, Home, I'm Sorry Did You Say Street Magic, and What Dust Remains are all GMless games for groups. I'd also like to recommend Ironsworn and it's sci fi spin off Starforged for RPGs that can be played solo, GMless in a group, or a more traditional GM style.