You've missed the point of the comment that you've replied to. There's a well known adverse selection effect because the people who would pay for no ads are exactly the people who you most want to be able to serve ads to: people with lots of disposable income, and people who are power users who see the most ads.
As a result the actual amount that they would need to charge for an ad-free version is higher than the average revenue per user, possibly significantly so.
edit: you can look at YouTube premium for an example of this in practice. It's $16/mo for no ads. That's around 2-3x or more what their revenue per user is.
The amount of money you spend doesn’t affect your disposable income, just your savings (beyond calculating interest). Unless we have different definitions of income or disposable.
As a result the actual amount that they would need to charge for an ad-free version is higher than the average revenue per user, possibly significantly so.
edit: you can look at YouTube premium for an example of this in practice. It's $16/mo for no ads. That's around 2-3x or more what their revenue per user is.