[yoyohello13]

The only reason there is one Linux kernel everyone uses is because of the license. If it wasn't GPL2 there would be "Microsoft Linux", "Google Linux", "Oracle Linux" all with different features and potential incompatibilities. At least with the GPL2 license those flavors have to contribute changes back upstream so everyone gets the benefits.

[wizzwizz4]

They don't have to contribute them upstream: they just have to give their users the permission to do so.