Go is well past the point of it mattering whether Google continues to use it or not. I don't think Dart or Flutter are.
And Dart's more of a barrier to that level of adoption than Flutter itself (if it were somehow language-agnostic, or a multi-platform JS framework even). Tauri has mobile support coming, and once it does with some level of polish, it's harder to imagine Flutter ever getting that popular? It would be trying to convince 'this is a great framework, this is the one you should choose [but sorry you need to learn Dart]' versus 'use whatever [JS] framework you want, you probably already have a favourite'.
And Dart's more of a barrier to that level of adoption than Flutter itself (if it were somehow language-agnostic, or a multi-platform JS framework even). Tauri has mobile support coming, and once it does with some level of polish, it's harder to imagine Flutter ever getting that popular? It would be trying to convince 'this is a great framework, this is the one you should choose [but sorry you need to learn Dart]' versus 'use whatever [JS] framework you want, you probably already have a favourite'.