It's one of the two reasons why Linux isn't ubiquitous on the desktop. (The other being open source doesn't provide enough incentive to do the boring unsexy work)
Fragmentation kills support. Imagine non technical users searching for help on an issue. First finding articles on Windows, then version X, then getting 'only applies with piece X, Y, Z installed'. That's already a problem and the suggestion of making Windows less 'batteries included' would make it harder for the mainstream users, who are the bulk of users.
Fragmentation also kills products, it increases development costs, reduces velocity etc.
Microsoft knew/knows how to make a better product, they just don't choose to because they evaluate they can make more money by screwing consumers over.
In my opinion we need regulation regarding anti-features. It's not perfect but it's the approach that is the answer in the non-digital world.
So make all features modular with advanced user being able to remove and get a lean and mean OS.
We want less, we want speed.
P. S. It is about time to upgrade the File System. It is too slow...