No it’s really payment processors.
There have been multiple successful ad-free websites in the past. But they still need revenue to function. Revenue their users happily pay.
But then Visa or PayPal or whoever is handling the transactions starts to pay attention and then all the sudden there’s new rules in place or else they hike fees or just stop processing payments altogether.
And on the Internet, there is no true alternative methods of payment (hint: any viable methods are quickly suppressed by those same payment processors).
So the only way any website gets big is left to the whims of advertisers or payment processors (usually both).
I have no idea why we as a people are somehow fine with private companies having a complete stranglehold on all significant online business. Why we’ve allowed the government to privatize digital transactions, subject to very little rights or protections. It’s allowing private corporations to massively suppress free speech, commerce, and social gatherings in the digital sphere.
Honestly our supposed freedoms are more and more limited these days because they only apply to public spaces, but there’s been a continual erosion of ‘public’. Where is the modern town square? If the only place you can practice your ‘rights’ is almost nowhere, do you really have those rights at all?
The government should be mandating that ‘digital infrastructure’ (ISPs, data centers, payment processors, etc) are neutral and can’t be utilized to bully others out of business. That their privileged position also comes with extra responsibilities and restrictions so you don’t have the digital equivalent of cutting off water to an abortion clinic because the water utility is pro-life.
As soon as any one instance gets big enough and needs to get funding, the payment processors will crack down on allowed content. Don’t like it? Tough luck in receiving the money people are trying to send you.