It's like people are trying to misinterpret.
Liftoff is strictly using Lemmy's free API and for the developer 5 users or 5M users doesn't make a difference to his expenses.
The Sync developer is obviously trying to do something more ambitious.
It's great that we have FOSS apps that do a decent job but we shouldn't look down on developers who put a lot of time, effort, and money into something expecting to make a return on their investment.
I don't like data collecting either but I accept that if you want to offer a free version - it's inevitable. What I hate is when you're not able to pay for ads to go away.
But I might be biased as I'm a developer myself and would hate to put 8-9 weeks of hard work into delivering a great app and then get hate for wanting to get something in return for that work.