Have you ever worked in a restaurant? I've worked in multiple.

There's a reason Karen is a meme

There are a real lot of very entitled people in the world that will complain on review sites and their opinion is not really justified. The only barrier is having an account and picking a number of stars.

In the past you had to be a restaurant reviewer, like you worked for Zagat or something, so there was a barrier to entry.

The same thing can happen to Uber and Lyft drivers too... If you are very unlucky and your first ride gives you a bad review pretty much forget about it.