Do Nutkins still drop?

[Alberel]

All this tells you is that not a lot of people are doing treasure maps. What do you expect when the only real reward from them that's worthwhile are incredibly rare minions? In most cases you would probably make a bigger profit selling the maps. People don't like doing something for nothing and that's pretty much what treasure maps are unless you get really lucky.

This precisely.

The only thing of value from the maps is the rare pets and unless you want to take your chances with this game's notoriously cruel RNG you're actually better off just selling the maps and using the income to buy what you want. I'm guessing more and more players have noticed this now which would be why so few actually do the maps any more.