To be clear, I am not a part of the foundation. You can read about it yourself on https://foundation.rust-lang.org/ (with the bylaws being at https://foundation.rust-lang.org/policies/bylaws/ )

The foundation's stated mission is to steward the intellectual property of the Rust project, and assist it and its maintainers. That often means things like "paying for legal support" and "paying for CI" and such.

The Rust project is the thing that's existed for years, and makes all of the decisions about what happens to Rust technically. The foundation has no position in that hierarchy, and sponsoring the foundation does not get you a seat on the teams that accept RFCs.

> a regular sponsorship would have a been more enough in this case.

I'm not sure what distinction you're drawing here between "regular" and not. Maybe that they would only want a lower tier sponsorship? I don't know, you'd have to ask them.