If you bother to read the license agreement, you will see that it is Microsoft who determines what software this tool will remove from your computer. That is, it can and will remove any software that Microsoft thinks is not appropriate. That is why they need a new license agreement, because that is not within the normal license. Yes, it may do something about viruses as well, but it is mainly a tool for Microsoft to control what you can and cannot install on your computer. With your approval, because you signed the license agreement.
Big Brother on stereoids.