It sounds like you're describing why they have a monopoly. If you want to argue that they don't have one, you would need to point at an alternative with even remotely equivalent content. (Edit: Even a paid alternative would be interesting; last time I looked Nebula only served a tiny subset of equivalent content)

(There is perhaps an interesting discussion to be had in how they got/keep that monopoly; certainly I'm open to users not wanting to pay being a factor, but that seems like it would quickly devolve into "well Google dumped an absurd amount of money into them, killing off even the possibility of competitors" which is... even worse, in terms of being an unnatural monopoly)