No, fd does not aim to be a drop-in replacement for find. It was actually designed as a "user-friendly" (I know, I know...) alternative to find for most of the use-cases: "fd pattern" vs. "find -iname 'pattern'", smart case, etc. Also, in my view, the colored output is not just a way to make it look fancy, but actually helps a lot when scanning a large output in the terminal.
The speed is not hugely important to me, but I wanted it to be at least comparably fast to find (that's why I decided to try out Rust for this project). Otherwise, nobody would even consider using it.
I know that it will not be for everyone and I also know that it's a lot to ask someone to learn a new tool, but I'm happy if there are some people that enjoy using it. I certainly do ;-)