I agree with you in principle, and feel like tmux was written "for programmers" and therefore the author(s) felt it more important to be consistent than usable. For instance: I'm pretty sure with `tmux list-sessions` because the command inside tmux is `:list-sessions`.
It wouldn't be terribly hard to write a wrapper for the command itself that works the way you want it to. As simple as it seems, I think that would probably be something useful to create and release.