Yes, human tails are hairless. Here are photos of vestigial tails on humans.
Sometimes our body tries to include traits of our ape primate ancestors. Vestigial tails are not that uncommon. They are typically surgically removed from infants in 1st-world countries.
Years ago, I realized DBZ would be way weirder if their tails were accurately hairless....
I imagine you'd either have to sit on it, which is probably painful (maybe likely to even break it), or wear modified clothes and dangle that shit free for the world to see. Personally, I wouldn't like either of those options.
Technically we all have tails already. However they are made entirely of bone and aren't long enough to stick out. Really all they do is make sitting on hard surfaces uncomfortable and try to dig their way out of your ass when you do situps without a mat
I want a thick, prehensile tail that's at least 2/3rds as long as my body. I want to be able to use to hold things, hang upside down like a opossum, climb trees, and slap the shit outta Greg from work when he irritates me. That's the kind of tail I wish humans had. I don't care if it's furry or smooth. I'll crochet a tail condom if I need to.
I've got some furry friends and there's a whole spectrum. You can run into everything from the mostly human with some animal features like the kemonomimi trope to full anthropomorphic animals. Depends on the person really.
We used to have tails at some point in our evolution. Some people even continue to be born with one very rarely. Back when we all had them, we were probably a lot more hairy, but those born with one now are hairless.