There are other compilers in development, and they're able to coordinate with these documents. There is of course always more work to do, but it's really not as far away as some people believe.
US corporations have massive influence over Rust since they bought seats on the board. Speaking of the board, it seems to me it’s all US based.
The company working on the official spec is a Berlin LLC.
US corporations also have massive influence on the C and C++ specifications, just look at the brouhaha around Bloomberg and contracts for C++, for example.
And the Rust Foundation does not author the specification, the Rust Project does. So in many ways, companies on the Foundation board have less direct influence than the companies who send their employees as representative to WG21 or similar.
https://isocpp.org/wiki/faq/wg21 is still very US skewed, but much more diverse than both https://www.rust-lang.org/governance/teams/lang and and the foundation. The latter does influence the direction of the language: https://rustfoundation.org/safety-critical-rust-consortium/
And sure, corporate influence is worth talking about, but the point is C++ isn’t free of it either.