It seems like an unfortunate point of centralization that Bitcoin's "official" spec is maintained by a single organization in a language that makes it difficult to run alternative implementations while ensuring consensus.
Discussion
Computer science is what makes that difficult. Getting bit-for-bit compatibility is extraordinarily difficult.
It is easier to try to reimplement a specification written in code than it is to reimplement a specification written in English. The former can at least be tested by actually running the code. The latter will always be unclear.