There's a bunch of different efforts in this direction, but ultimately it's actually a very hard (technical) problem. There's no way to get confidence on the data unless you have control over operator systems (and no one wants that) or you're running everything in a TEE (won't happen from technical+speed perspective).

I know it's a hard technical problem but it needs to be addressed. We can't fly blind as a community.

Also the systems monitoring diversity should be air-tight. Not like this one here where it does not even add properly up to 100%.

Gives zero confidence on correctness.

Eg improve reporting at CL: https://github.com/ethereum/execution-apis/pull/517 (doesn't help that much and can be easily spoofed / lied to)
Another thing being done: network analysis of nodes that we can then cross-check against self-reported data.
and...

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