This is not true. Open your user folder and there will be tons of dotfiles. If you use git with ssh or Rust (.cargo) or C# (.nuget) and many other tools. In fact, even .config is started to show up now.
Are you using windows? I feel like dotfiles are much more common on unix-like systems. For me I've got dotfiles for zhs, ssh, git, two for my window manager, vim, and much more. I've even got one for nethack. I quite like it, I get new laptops up and running and feeling like home in a matter of minutes.
Yes windows. That’s my point: dotfiles are synonymous with ”configuration files” on Linux/Unix but not elsewhere so making a ”cross platform dotfiles manager” seems like a contradiction almost.
By historical accident, Unix-like shells tend to hide by default files whose names begin with a dot. This led to programs naming their config files ".$program_name" and throwing them into $HOME. It's no longer cool to do this, but the tradition lives on.