Tyneside v Teesside - just can't see anyone getting mixed up. If they don't know then they are going to use Google/journey planner and are going to need to specify which airport.
A student is the most likely to know that there are loads of universities! And very likely to use Google/journey planner. Good chance they have near zero geographical awareness and are using google/satnav to get everywhere.
Which only illustrates the point.
"University" simply won't be the university the vast majority of students and parents are meaning when they consult a journey planner for their first time travel needs in the Tyne and Wear region.
Newcastle "Airport" is nominally local to very few people in Tyne and Wear (the vast area covered by the Nexus journey planner and Metro map) in a way that even Teesside Airport could not be considered local.
"Airport" is only actually even accessible as a single journey to half of the stations on the Metro, and even though it's a single journey, taking the Metro from Sunderland to the Airport, with heavy luggage and stopping at every stop, is as much of a pain in the ass feels like you're travelling half way across the country experience as it was when taking the Piccadilly Line to Heathrow.
London being London, they now have better options. But for the sake of illustration, let's forget those (and City Airport) and consider how absurd it would have been to have named Heathrow simply "Airport" on the tube map, as if that was what makes it local (being the only airport on the tube network, and the closest to the nominal centre of the region).
Sure, Gatwick, Stanstead and Luton are further away as well as not being on the tube, but for a large number of people in the "London" area, whether for reasons of speed, convenience, price or flight options, they're not going to bat an eyelid at considering any one of those as their preferred local airport, and would thus find it quite curious to see Heathrow named simply "Airport" on a tube map, even if they knew such a thing is only being done as a nod to locals, with everyone else farmed out to the journey planners to resolve the ambiguity.