For me, and I assume many others, vim is fun. It sort of gamifies text editing. There's always new things to learn, and executing advance keystrokes is satisfying. Once you know them, moving to other IDE's is a pleasure because they all offer a vim mode (with varying levels of compatibility). Personally I use vim / emacs + evil / jetbrains depending on the task.

But if you don't care about that aspect, I agree with you, just stick with the boring thing that works. I don't think vim really saves me much time in the long run, but it sure makes my daily tasks more fun.