Now you need to say the same thing about App stores. Since 99% of the population uses Google or Apple Apps, is it still perfectly reasonable to consider these gateways ontop of the Internet or are they "the Internet"?
So to answer your question, my overall point is that a redditor's experiences are generally doubly enshittified before they actually get to the content. First via their ad tracking and privacy-leaking-as-default mobile device, and second via their small 4" screen and just as horrible reddit app. They dismiss these two transparent enshittifiers as "just part of the dead Internet" when it's clearly not.
It is tragic that so many people are unaware of or uninterested in the fact that they're not allowed/encouraged to run software that Apple and Google haven't given them permission to use.
I'm really not sure what argument you're trying to make here.