To be honest, the data collection was enough to keep me on Connect instead of Sync. With that being said, I was excited for the release of Sync. It wasn't my primary app on Reddit, but having developers for Lemmy apps is great, and the developers who had successful Reddit apps already have a solid idea of what to do. Sync is not finished, so there are valid complaints to be made! But it also already looks more polished than Connect in many ways, in my opinion.
In terms of the price point, I don't actually think it's unreasonable. There's a one-time lifetime purchase available, and as I understand it the app is being developed by a single developer trying to support himself. I get that the price might be outside of some people's casual spending range, but luckily there's a free version with ads (and many, many other free apps without).
I have no intention of using either, but I'd rather pay 50¢ to have less data sold to third parties. Although the app you linked also says it contains ads, so I'm not sure its play store page is accurate.