Sure it is - the vast majority of webapps are glorified CRUD. I'm not saying there are not high performance use cases. I'm saying if you list every app, most of them would be fine with exclusively JavaScript, and for the rest you have careful use of WASM or backend delegation to a faster language.
And to the author's point, something slow in JavaScript is better than nothing at all.
If we're talking about a glorified form/CRUD app, no.
For web apps proper, that's not really the case.