Morally, Uber should be allowed to charge whatever they want to. No one is forced to take an Uber.

But in practice Uber does face at least public scrutiny. Eg when there was a hostage situation in the Sydney city centre a few years ago, everyone wanted to leave and Uber's surge pricing kicked in automatically (no human at Uber even knew about the hostage situation, at least there was no human in the loop).

Of course, this was exactly working as intended, but it was a bad look, so Uber retroactively made all the fares out of the city centre free that day.