Maybe GP has just never taken one to/from the airport? It's really not that common to do that in many places outside of the US. In many European cities, public transit is often the fastest way to get to/from the city center from an airport.
Elsewhere, Uber is just not great compared to taxis, and supply can be minimal:
I've had to take an Uber recently for work [1] , and I effectively had a choice between one driver that would ask me to please cancel from my side because they didn't want to go to the airport, and another driver already at the airport (with Uber blatantly lying that they'd be here to pick me up in "10 minutes", when the ride takes 30 without traffic).
[1] Expensing a taxi invoice is more of a hassle. On top of that, often the card terminal mysteriously and completely unexpectedly breaks down at the end of the ride in taxis in some places, and expensing cash payments is even harder.
But they were banned in my country years ago.
Taxis and humans queue up against each other in the countries I've went to.