I think the D&D Beyond data is the best available, so yeah, as far as we can tell dragonborn are, like, middlingly popular.
Without being told I'm guessing Gnomes, Half Orcs, Halflings are in the eh category.
Gnomes had niche protection in AD&D they were quite good mechanically at least.
Power creep and not an Elf doomed them.
Elves always popular think it's just as simple as pretty human. Then you've got short human, mini human, ugly human.