Seems you are responding to the wrong thread here. User the_af was asking me why I replace a machine and I answered with some reasons specific to me. This was a deeper dive in to the point that some people don't need to upgrade at all because they don't do anything different between day 1 of their usage or day 1780. And they don't need to because the laptops of the last decade don't fall apart as much as they used to and a Mac specifically tends to work well during its entire lifecycle. This is also why there aren't as much people interested in modifying their computers mid-lifecycle.

While I bet that there are a lot of people that do want to modify their systems, they are such a minority that it's not very logical for a large multinational to invest in that to the detriment of other goals. It might simply mean that you are not the target audience for their product(s).

Some other manufacturers/brands have the same, while others do a mixed portfolio to cater to smaller groups as well. We also have large manufacturers that cater to the classical enterprises which still run on the old idea that you need a fleet of identical machines and then swap out parts all day long, so machines that have facilities for that exist. Most notably Lenovo, HP and Dell do that.