I don’t know about Uber, but Apple has spoken about collecting similar data and they anonymize it by slicing the route into a bunch of little pieces, throwing out the beginning and end of the route, and anonymously uploading the bits in the middle.

See “Probe data and privacy” section here: https://techcrunch.com/2018/06/29/apple-is-rebuilding-maps-f...

There's no indication that they are submitting the full trip trace. If they only submit 500 meter long traces, it may he sufficiently anonymous.