To choose one of your examples, when I want to paste, my fingers know C{md/trl}-v, so C-y is not familiar. But it's not just copy and paste, I want keys for things like find, find again and replace to work about the same in all the apps I use, notably browsers, where I spend more than half of my time. Keys like these are used by most Mac, Linux and cross-platform apps. I know the Emacs commands aren't exactly the same — they're often more powerful, with more options for different types of find — but editors like VS Code and Sublime Text also have more powerful find than a browser, for example, but their keybindings are much more similar.