If your target is 4.7, every asshole who gives you 4 stars because "there's always room for improvement" or "5 means excellent and I wasn't that excited about it" has to be balanced by at least three more who give it 5 because they recognise that the wage slave has no power to make it better than they did and it's unreasonable to expect the wage slave to inject joy into their day.

most people don’t actually shout at people

Depends on the company. Some companies give people a ten cents raise, an hour's training and lots of stress and targets for being a supervisor. I don't know whether shouting at the other wage slaves is the intended behaviour, but it's frequently the outcome.

It's great that you don't have experience working for places where the fear is used for control, but that doesn't mean it doesn't happen a lot.

You may say "if you don't like it, feel free to get a different job", but that's exactly what management say, and there are plenty of people on whom that fear works.