It's even a core point for Carbon, their hopeful C++ replacement
Under language goals on their readme,
> We also have explicit non-goals for Carbon, notably including:
> * A stable application binary interface (ABI) for the entire language and library
> * Perfect backwards or forwards compatibility
There's also this blurb
> Our goals are focused on migration from one version of Carbon to the next rather than compatibility between them. This is rooted in our experience with evolving software over time more generally and a live-at-head model. Any transition, whether based on backward compatibility or a migration plan, will require some manual intervention despite our best efforts, due to Hyrum's Law, and so we should acknowledge that upgrades require active migrations.
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.
I find this to be the case with a depressing amount of Google code. They do not seem to have a culture which values not breaking their users' code.