I do not believe that knowing ASM would even remotely translate into the ability to optimize web pages for latency: understanding high-level concepts like TLS,

I do not believe that knowing ASM would even remotely translate into the ability to optimize web pages for latency: understanding high-level concepts like TLS, HTTP/HTTP2, and being to understand JS engines seems far more applicable. You also seem to be making the assertion that you cannot understand how a CPU works without knowing ASM, which seems equally spurious.