Linus Torvolds and the folks at kernel.org work to continually improve the kernel and ready it for each release cycle.
Ubuntu and other distro maintainers take that work and make sure that they are shipping to you a compiled kernel(s) that dependably works with all other software on their distribution.
GPL is designed to protect developer rights, not user rights.
If google packaged your linux distro and sold it through the play store bundled with their own apps and sandboxed everything and called it chromeOS, your rights would not be any better protected.
Security and privacy involves users making informed choices to protect themselves, full stop.
How I got python linting working in neovim