The bigger benefit is making them easily repairable. This HAS been done, older thinkpads stayed in service way way longer than most of their comparable laptops simply because they were so serviceable.

One thing the framework does right is their charger setup- you are likely to break and wear out the charging port on a modern laptop- and when that happens on a framework you simply swap out the module and keep going. This is a much bigger deal than replaceable / upgradable motherboards, but keeping it all compatible makes parts easier to source for those repairing, not upgrading. (I’ve seen plenty of laptops discarded for a bad charging port, making it repairable without even opening up the laptop is AMAZING. I no longer have a modern thinkpad because they went to a delicate usb-c directly soldered to the motherboard instead of the old wired in charging port that you could repair by unplugging the broken one)