> I am confident a human and about 5 minutes with chrome debugger would yield better results
It really depends which human. I've worked with very few engineers who were good at this sort of optimisation work. A depressingly large percentage of people who make websites for a living don't really understand how http requests are really processed, or how to read and use the chrome profiler and benchmarking tools.
Claude isn't as good at optimisation work as someone who really knows what they're doing and goes deep on a problem. But I'm optimistic that it will help plug a capability gap in teams which don't have this sort of expertise on hand.
(That said, the chance that people actually learn this stuff is going to also go down if people get used to outsourcing this work to claude.)
The job of making a website is a large part something that should be given to people who have majors in art, English, and similar things. Well, there is some value in an engineer to build the whole site, but that's more of a framework task. The vast majority of the content is not an engineering thing to do. It is a job of people who are experts in language, art, journalism, those types of things that have very little to do with engineering.
In short, if most of the people working on your website could do those things you named, you have a problem that you have hired the wrong people for the job.