I don't think that is fair to taxpayers that don't use public transport because they walk, bike or use a car.
It makes society better because it means less congestions on the street and less pollution, it makes it fairer for those that don't have a choice (because they're too far from work to bike or walk, because their city does not have have the right bike lanes, etc ...), it's the definition of what taxes should be for in a developped society, imho.
I'm happy to pay higher taxes for it, despite not needing it since I work remotely and have most place I go to within walking distance by living in city center.
Not that the article here is for kids (and in particular for Paris) so my comparisons is not that great I admit but still, living in a rural area I've spent my entire teenage decade dependant on public transport to go to the school my parent wanted for me, to go to "the city" see my friends/visit places/go to the mediatheque where they had computers (!!!), and along with the food cost at school it was a major expense for my parents, that they would have had to cut on if one of them was unlucky and lost his or her job.
So it still rings very true to me. But again, given it's about Paris, my exemple is not that great. You probably realized I would probably be ok for it country wide though.
Also, there must be plenty of less obvious effects. E.g. Uber Eats or other kinds of delivery services can get cheaper, if couriers can travel across the city all day for free.
And Uber Eats wont use public transport, it is very slow compared to an e-bike or scooter.
I travel often to NYC and it doesn't seem much different to those of many major European cities, at least in terms of reach.