Is there a definition of “fixable” that people agree on? I had a Dell XPS many years ago where RAM and HDD were socketed to the motherboard, but the build quality was awful and the hinge attaching the screen to the body snapped during normal use. That part wasn’t “fixable”, but I felt like it should have been. I couldn’t have cared less about more memory at that time.

There’s the framework computer, but numerous reviews suggest that thing sucks too, even though it is “very fixable”.

Should all parts for every computer just be available at a big box store or Amazon? What if it became possible to attach more RAM via USB-C, like how the SSD can be expanded via the same? What’s the goal here?

This is a pretty bad article because the author didn't really consider how product design works.

The new M4 MacBook Pro products are not a new design, they are a spec bump in the existing design. Making the kind of changes they are asking for requires a more extensive product redesign that only happens on Mac systems every 4-5 years or so.

Apple's full redesign of the Mac mini does show a slight increase in the modularity of the system by socketing the storage on a (proprietary) module.