I would've preferred dart to be more opinionated like golang but its not, you can literally write in almost any style and one advantage of that is if you have experience with any modern language, you should be able to write dart with ease.
Dart was actually really opinionated right from the start. Type annotations that has no bearing on execution; reified generics and dynamic typing at the same time; mirrors and noSuchMethod... even having semicolon - as opposed to not having it. These are all strong opinions about language design. They might not align with what is considered "modern" these days, but they are all opinions nevertheless.