Are you talking for direct, by credit card payments that somehow you can't cancel? Can you explain a bit?
As for the darkest of dark patterns - give Adobe some money and see what happens.
Think gyms where you refuse to cancel even when you are physically there in person with someone to yell at and imagine trying to do the same online where there's not a phone number, or a phone number with a 1 hour wait and a CSR paid based on if they can successfully not give you what you want
they are just there for the captive network effect, which will take a hit the second or becomes a freemium or ad ridden service.
those are literal public forums people go to expose themselves. you don't have a very good point.
If I understand it correctly, people use it mainly because MMS was a dumpster fire and WA was the first platform which got critical mass in most countries, which it achieved by being both pretty good overall and by being cross-platform.
The encryption is a nice bonus that everybody likes, but you can't prove that is a primary or even major reason why plumbers in India, tour guides in Dubai, and school parent groups in the US all choose to communicate with it, personally and professionally. If anything, I feel like Signal must have by now poached a good number of the people whose main concern is "How encrypted is it?"
Also, Gmail is not a public forum and people don't mind that it's 'ad-ridden' either.
i don't think people join because it's encrypted, but they wouldn't use when it's not. it too can became the dumpsterfire that sms was/is.
There must be some some number that makes it viable to have free users and paid users. For games, the free users are usually those who provide the "content".
People usually demonize freemium games but IMHO its much more benign than extracting huge sums by artificially making it worse and sell attention.