This isn’t true in Flutter. They literally bake into the CLI with each release which will automatically identify and upgrade any parts in your application using old APIs without any intervention required. It’s literally the opposite of what you’re describing here.
What you described is Google breaking your code constantly but also giving you a tool to automatically fix the code they broke, so it fits well within the general philosophy of not taking breaking changes seriously.
It sounds like the tool might make the specific case of flutter version upgrades easier though, if the tool works well, so that's nice. Most Google software doesn't come with similar tools.
There is nothing about that that allows you to come to a good faith conclusion of “doesn’t take breaking changes seriously” when they literally do all of the work for you.
https://docs.flutter.dev/tools/flutter-fix