Some people think like this: if i write an app and come back in 10 years, is it still going to work, compile, and be possible to update? By that benchmark very few platforms are acceptable, and they are mostly first party.
That standard makes sence if you have a rigid hardware-like approach
Yeah, that makes a lot of sense for certain platforms. I've spent a lot of my career working with enterprise customers, some of whom are comfortably running 20 year old software written with something like WPF. And in general, that would be true of Flutter too -- on a platform like Windows, it will work at least as long as the underlying Win32 APIs are available.
(Of course, that's not a viable test for most mobile frameworks. I suspect that an iOS Xcode project from 2011 would not run without rework, nor an app written for Android Honeycomb.)
Flutter is open source, which provides some automatic measure of protection against obsolescence. And companies like Toyota who are building it into embedded systems like cars that will still be around in 20+ years.
That standard makes sence if you have a rigid hardware-like approach