I think the reason is more that the goals of the C committee align better with the goals of C programmers (which is a language that's a tool and not a playground for language designers).
Unlike C++, C also remained a simple language (which is definitely a side effect of the "conservatism" of the C committee).
That's what he means; like the puddle which marvelously fits its own hole, anyone for whom C in all of its aspects is not very close to optimal has long ago moved to another language.
Unlike C++, C also remained a simple language (which is definitely a side effect of the "conservatism" of the C committee).