Yes, there is very often a need to quickly search in source code (to figure out how something works, to discuss about it in places other than GitHub issues...).

Yes, there is very often a need to quickly search in source code (to figure out how something works, to discuss about it in places other than GitHub issues...). Cloning is usually fast but not with very large repositories, and you might not even have enough space on your current device to clone them. By the way if a lot of people will end up cloning everytime instead of logging-in (after all logging in to GitHub is a pain with the 2fa) I don't think their systems will have less load. And not everyone might want to have a GitHub account