Flutter is not as bad, if you still can code in Swift ;)
Oh dear, I can never forget those discussions about what is better, how should I make the app etc etc.
The answer is always the same: it depends.
but you don’t have to take that decision now.
The best in flutter is that you can easily make native UI’s without having to recode them to all platforms.
But as we know, iOS devs hate to code logic in the another layer. We love to feel close to hardware that’s why. You should try to use MVVM model where whole Model is stored Swift Layer.
In this solution Flutter could be used only what it did’s the best. Representing views, also it allows your team to have only one frontend for all platforms 😉