AirBnB removed cross platform from their code base, even though on paper it should had worked. Now, they used Reactive Native — but at the end they also talk about flutter
"I think people really seem to be really enjoying Flutter. I think that it's really important to understand that even if they solve some of the technical problems, maybe the performance is better, maybe the IDE is better, the language you like more, you're still going to have a lot of the same organizational problems."
"I really don't anticipate us adopting Flutter, Xamarin or any of these cross-platform frameworks any time soon".
transcript:
https://softwareengineeringdaily.com/wp-content/uploads/2018/07/SED639-React-Native-at-Airbnb.pdf