There are shitty things in the world. Some of those shitty things are profitable. Many many profitable things are not shitty. It is entirely up to the individual whether they want to be a part of the shitty things, particularly when the individual has the privilege of being in demand. If you're a software developer who decides to work on scammy tools to make money, that's fine, but don't expect me to not factor that information into how I decide what kind of person you are.
Further, YC is supposed to be innovation, and disrupting entrenched markets. Profitable innovation and profitable disruption, yes, but as I said, there's more than one way to make money, and the way YC claims to want to make money is in those ways. Bundling crapware with Windows installers is not a disruptive or innovative way of making money. It would be classified as a shitty, scummy way of making money that has been happening for years. Many of us here that admire YC admire them because we think that innovation and disruption ultimately are beneficial. So when YC, instead of funding innovation and disruption, funds scumminess and shittiness that's been happening for years, we are disappointed in them.