[levitate]

I would not say that React won over svelte because of simplicity. Hate what you will about implicit behaviors in svelte, but the syntax is simple and intuitive.

React won by being early and different. Svelte came out three years after React and got (unfortunately) steamrolled.

[paulddraper]

There two notions of "simplicity."

One is that the implementation is very simple/transparent, e.g. C.

The second is that it allows users to have very simple code, e.g. Python.

React is mostly the first with a bit of the second. Svelte is the reverse.