No "Monero Foundation" exists at this point because nobody has taken the initiative to create one.

The priorities and actions of both the Bitcoin Foundation and the Ethereum Foundation have been criticized by large parts of their respective communities. Sometime foundations can develop conflicts of interest with the community they were designed to support.

So far the Monero community has seemed more receptive to the idea of supporting projects with a more specific and well defined purpose via the Forum Funding System or "FFS". The closest we have seen to a "Monero Foundation" so far was the Monero Economy Workgroup or "MEW" and it was subsequently abandoned.

The Monero community seems very keen on not centralizing decisions more than necessary. In the short term, it more likely for more specific tasks to be funded by the FFS rather than a "Monero Foundation" being created with undefined or open ended objectives.

If any private party wants to create and fund a Monero Foundation on their own they are free to do so. The degree guarantee of community support (or lack thereof) would depend on its purpose and execution of its stated objectives.