But it's common these days to confuse reader to make self promotion for their tech/services
A huge amount article's on Medium are similar to this one, they stay at the surface and don't really bring anything new to table.
EDIT: I'm not so sure as to what you mean by "staying at the surface," though - I included examples of patterns that are common in React, their analogues in Flutter, and the reasons why said patterns may or may not apply well in Flutter.
Sounds like the writer hasn't too much experience, so be kind :)
FWIW I’ve found the most prosuctive front-end combination to be React + Typescript, which has the benefit of being seamlessly interoperable with JavaScript, really excellent at capturing common errors, and allowing the type system to be exploited for much more expressive code. YMMV of course.
Is TypeScript better in that regard?
Sounds like an editor issue. Have you tried it with something like IDEA/WebStorm where there's a bit more code intelligence?
Inheritance has it's place in the toolbox.