I have a USB stick that I can use to reload Windows at any time. I downloaded Windows and put it on the USB key using their utility and if I were to replace a drive, my OS eats itself, etc. I just grab that stick. It really should be that easy with macOS too.
Most people don't have multiple computers and most people that own a Mac are unlikely to have two of them.
Most people don't have multiple computers and most people that own a Mac are unlikely to have two of them.