What are the differences between the linux kernels for each distro? Are there any differences like between say Fedora and Arch?

Interested in the differences between kernels that a distribution uses, would like to know what changes they make to kernels if any at all. Like is there a performance benefit to a fedora or arch kernel over a debian one? What about Clear Linux which is an Intel Project which works on linux and makes Clear more performant. CachyOS uses these patches as well but do other distros? Obviously there is a difference between the type of kernels use like LTS etc but im more interested on the smaller tweaks each distro makes and why. Thanks!