Isn't this a bit disingenuous given Vue's usage in true, scalable production capacities? I'm not the expert but companies like Netflix, Adobe, and GitLab have Vue deployed at scale. Since when was "quick" synonymous with "not sufficient for serious development"?
To my understanding the biggest reason GitLab chose Vue was because they were able to easily mix it in with their existing stack. That's part of what I was referring to by "drop-in". You can do the same with React but it's more heavyweight unless you plan on porting the lion's share of your app to React.
As for the others I'm not sure what they're using Vue for specifically and can't really speak to the technical reasoning behind it. I'm not saying that you can't do serious development in Vue but rather that all else equal I will guide teams to adopt React, mostly for the better developer ergonomics.
There's nothing trivial about being "drop-in". Usually these are complex apps running on traditional web frameworks and/or use server-side rendered pages where Vue excels in adding front-end interactivity because it uses HTML templates by default (with that HTML coming from the server).
