When you're writing on an architecture with only poor C compilers, it makes a lot of sense to prototype in C and hand compile it. For example, as a hobby, I write on a platform where program memory is limited to 16k and the only available C compiler is sdcc, which outputs relatively large binaries.

So writing in C is fine for smaller projects, but those are easy enough in assembly anyway, especially on the old architecture designed for human-produced asm.