Earlier quoted context omitted.
Ideally you'd also get ad-free access to Twitter itself, which I would certainly consider paying for. Considering the annual per-user revenue is ~ 12USD [1], this seems like something that would be financially interesting to Twitter. [1] https://www.nasdaq.com/articles/forecast-of-the-day%3A-twitt...
The average across all users is $12, but I suspect the average over people willing to pay for Blue is likely higher than that. It's can be a Catch-22 in some cases. The same people most willing to pay to opt-out are the ones most coveted by advertisers.
On the other hand, I realize that services cost money to build and maintain, and if the subscription came with ad-free (and data-mining free! "ad-free - same great ad-tech data-mining flavor" doesn't count) I would definitely subscribe.