Their observations especially on Observables is very spot-on. We have quite a few "makeObservable(input)" in our code to make @Inputs observable. That the framework doesn't do it automatically is a bit of a let down.

Same about Reactive Forms.

Patching each @Output and @Input through a component by hand is also pretty annoying, especially if they change relatively often. A custom input field for a reactive form gets quite large due to all the in- and outputs.