No such thing as a free lunch. Telegram hasn't done a very good job of eliminating the possibility of profit. The secret chat feature is actually a marginal us

No such thing as a free lunch. Telegram hasn't done a very good job of eliminating the possibility of profit. The secret chat feature is actually a marginal use case. By default messages are readable by the back end. In fact, group chats are also reasable by the back end always, and any conversation which can be accessed from multiple devices. And last I heard, the official windows desktop app does not have secret chats. All of these messages are the normal use case on telegram. And the text is being indexed by the back end for easy searching capabilities. So essentially telegram has built a search engine for the conversations of tens of millions of people who are slightly more paranoid and want a secure messenger. Not only that, many of the tens of millions have shared their entire address book with names and phone numbers because the official clients required them to. If they're trying to avoid having valuable information that someone would pay money for, they're not doing a very good job.