I started paying before they were bought, I might even have paid twice and I loved it. Would happily paid for a few famuly members as well.

Also there should be a huge possibility to increase revenue by selling API access (think appointment reminders etc as well as the whole bot ecosystem).

When Telegram started they talked about price and I think I remember being unconvinced. I wanted to pay. As we (used to) say here on HN: if you're not paying you are the product.

(Of course now we have learned that some companies charge us and still sell our (meta)data and advertise to us.)