Well I'm on a 2016 macbook air, 8gb RAM and doing web programming everyday. 3 phpstorm windows, sometimes Photoshop open, more than 20 tabs in Chrome, iterm, figma, paw... Honestly it runs pretty well and I was waiting for this update.
PHP Dev often means some sort of local server running too.
compilers are often compute bound (certainly on SSDs).
web servers are almost never compute bound.
It's OK to geek out about hardware, if that's your thing. But it's not really necessary for most people -- even programmers.