Netflix buffering issues: Boxing fans complain about Jake Paul vs. Mike Tyson

This is probably a naive question but very relevant to what we have here.

In a protocol where a oft-repeated request goes through multiple intermediaries, usually every intermediate will be able to cache the response for common queries (Eg: DNS).

In theory, ISPs would be able to do the same with the HTTP. Although I am not aware of anyone doing such (since it will rightfully raise concerns of privacy and tampering).

Now TLS (or other encryption) will break this abstraction. Every user, even if they request a live stream, receives a differently encrypted response.

But live stream of a popular boxing match has nothing to do with the "confidentiality" of encryption protocol, only integrity.

Do we have a protocol which allows downstream intermediates eg ISPs to cache content of the stream based on demand, while a digital signature / other attestation being still cryptographically verified by the client?

What you describe is called a CDN and has been widely used for 20 years.

there's Named Data Networking (went by Content-Centric Networking earlier). You request data, not a url, the pipe/path becomes the CDN. If any of your nearest routers have the bytes, your request will go no further.

I don't see it much mentioned the last few years, but the research groups have ongoing publications. There's an old 2006 Van Jacobson video that is a nice intro.