For an entire OS, this doesn't make sense. It does make sense for business critical software. We did this 20 years ago, even calling the subdir VENDOR, for some

For an entire OS, this doesn't make sense. It does make sense for business critical software. We did this 20 years ago, even calling the subdir VENDOR, for some 3rd party components. It's part of design, and even support of your stuff. What's new is containers and k8s. People will put more into that, for dev and critical sw. However, for full desktop or OS it's probably cargo-cult or hard to scale and maintain.