[Osmose]

You're right that it was difficult, that's part of why React caught on. But lots of apps did it anyway—its not as impossible as you make it seem if you take the time to write some abstractions around checking what needs to be done or centralizing all DOM operations to reduce the chance of other code modifying then. I worked on multiple complex web apps that did things like this. It's just tedious and error-prone.

[throwaway11460]

That's my whole point, though - it was tedious and error prone, so it wasn't usually done. Then React offered an easier and more performance way, that's why everybody jumped on it.

[Osmose]

If your actual point is that "The virtual DOM is faster than a slow-but-common pattern of DOM mutation" then, sure. We have different experiences in how common wiping out the entire DOM really was in apps not using frameworks but differing experiences is normal.

But in a comment thread of people saying the virtual DOM is not faster than equivalent manual DOM mutations you can understand why "The virtual DOM was faster than the DOM" got understood differently since it lacked that clarification.

[throwaway11460]

Well that's what React originally compared against. Sure, you could do it the manual, tedious and error-prone way to achieve similar performance, but that's not really interesting to React users.