I have a hard time understanding why this "drop in" experience is so important. Are you all writing simple contact us forms or something incredibly simple?
Any application that I've built which actually required a technology like Vue or React was a significant undertaking and a few hours getting up and going (not that either of them require anywhere close to that) is nothing.
I don't see how jQuery could have been anywhere near as ubiquitous if it had required a build step.
It makes experimenting easier for beginners, for people considering switching to it, for people who are already using it and want to try something outside the context of their existing codebase, for people writing tutorials and demos, etc.
The less bullshit to wade through when using a tool, the more situations it will be applicable to, regardless of skill level or project size.
That's just it though, Vue & React aren't for most web sites. There is no point in pulling either in unless you are building something much more complex than where jQuery would suffice. There is no need for a technology to be "ubiquitous", just that it is going to meet the demands your application has for it.
Actually vue is so small and simple you can just drop it anywhere. Even on non JS heavy website. It's a bit like redis. Low price. Always nice to have. Very reliable.
First, as a learning experience it's easier. In the HN bubble it's easy to forget most web project out there don't even have npm installed. I regularly train dev that just learn what ajax means.
Secondly, a lot of my projects just don't need anything else. If i have a 2 weeks contract with a client, i'm not going to setup webpack, a ci server and docker.
Having the choice to scale up or down is an amazing feature.
Any application that I've built which actually required a technology like Vue or React was a significant undertaking and a few hours getting up and going (not that either of them require anywhere close to that) is nothing.