Sync is fine. More good apps are better for the platform and really needed.
I personally will probably not use Sync for long. I remember using it for Reddit for a while but noticing the app was updated to slow which over time broke some stuff. Then I went onto the Sync sub and apparently the dev is a bit...sensitive when there's negative community feedback and then just stops for a year or longer or so. Good on him if he can of course, it's not like he has to cope with the internet but I've found other apps to be more reliable overall for Reddit. Let's see how this one goes.
You sound like the dev is just a Karen who can't handle criticism. But in fact that he was receiving death threats (literally) because he dared to change the UI and UX of the app in a major revamp (even though that version was in beta for months and nobody complained). That's why he stopped for one year
The higher price might also help him be motivated to update the app frequently. I'd still be on the lookout for alternatives and the hate sync is getting is pretty rash atm.
The price might also go down as his userbase increases. The amount of people using the fediverse doesn't yet compete with the previous reddit numbers so in order to live off it he needs more per transaction.
Sorry, I don't want it to sound like that. He can take a break whenever he wants but for me as a user I simply used his app, found it very good but over time it broke and when I checked out the sub I just saw that many people pointed to this and also that it has "happened before". I can't comment on all the drama that has happened with that community, I don't know. No biggie for me but I also kinda don't wanna deal with this and switching software too much. I started to look elsewhere because the Reddit app was breaking and there was no sign when the dev would come back and I landed on Infinity. So I will give that one a try too, see how these apps go and decide later on where I stay.
Also, I don't want to downplay it because it is still serious but you get death threats for everything on the internet. I've literally yet to see any drama no matter how big or small where this apparently wasn't the case. It's sad.