I don't think you can dismiss UX attempts to discourage checking the total fare estimate as "being bad at math". Yes, someone can work out the logical implications of various alerts, but no, human psychology doesn't always do this quickly or in a way that reaches a reflective equilibrium.

With that said, this is Uber SUV, with a $14 base fare[1], during a confirmed 4.4x surge, which really should alert the user to get an estimate.

[1] https://www.uber.com/cities/washington-dc