I don't think many are confused about why Anthropic wants to do this. The crux is that they appear to be making these changes solely for their own benefit at the expense of their users and people are upset.

There are parallels to the silly Metaverse hype wave from a few years ago. At the time I saw a surprising number of people defending the investment saying it was important for Facebook to control their own platform. Well sure it's beneficial for Facebook to control a platform, but that benefit is purely for the company and if anything it would harm current and future users. Unsurprisingly, the pitch to please think of this giant corporation's needs wasn't a compelling pitch in the end.