Are you really restricting the pool though? Most devs can't write or efficiently develop a GC. Learning a language is easy compared to writing a reasonably performant and correct GC. Anyone in this area worth their salt can pick up C if they don't know it already and, again, they probably already do if they have experience at this level.

I've been hearing 'C is dead' for fifteen years now, but it hasn't gone anywhere.

We've had compilers being written in their own language for half a century, but it hasn't changed the fast that most (and all the succesful ones with millions of users) are written in C/C++.