Completely removing the old kernels (rather than just removing from GRUB menu) is necessary because the modules use a very large amount of disk space (especially so when running on SSD). Constantly increasing disk space usage is precisely the kind of thing that people hate in Windows. Apt could solve this issue nicely, but only if Ubuntu actually removes the unneeded old versions.
Completely removing the old kernels (rather than just removing from GRUB menu) is necessary because the modules use a very large amount of disk space (especially so when running on SSD). Constantly increasing disk space usage is precisely the kind of thing that people hate in Windows. Apt could solve this issue nicely, but only if Ubuntu actually removes the unneeded old versions.