Loads of people complained, it just wasn't a very hard sell. PS+ has already been around for a while, and a huge number of people were already paying for it despite it being optional on PS3. If that many people were prepared to do it purely because of how good it is, then making it mandatory wasn't going to rustle many feathers.
It's like saying to someone "your bus fair was free before, but now it's 20p. Don't worry though, you get £1 of free cake every trip."








