Can’t just throw money at problems

This is why matching campaigns are often done, to see the market desire for something and matching that. Since no arbitrary amount will satisfy people that believe you have more, but this is the closest thing to it.

In any case this wasnt a matching one, just an analysis on what the Rust Foundation could make do with

You mean from M$'s bucket. It's something for the foundation.

It can surely grow if no issues occur. One of the worst things to do would be to drop some ridiculous sum on a project and expect it all to be used properly.