It's a hard call at end of day. If you want it to all be privacy respecting and open source and decentralised then you're almost guaranteeing you won't make money from it.

The alternative is ad based software that's free which is also garbage.

Hard to find the balance between the two, can't think of many examples if any that actually work besides just making a paid product that's very good and hope it's better enough than the rest to be successful. But even then you likely will have to cross lines because you're just relying on viral luck at that stage.