[eterm]

I think you're vastly overestimating how well engineered most SME web-platforms are when you say that the client-side is slower than the server side. There are a huge number of server-side asp.NET webforms/JSP/php sites out there which are far slower server side than client side.

And it's not just legacy code, new applications in 2015 are still using those mostly server side technologies without too much done on the front-end.

[UK-AL]

And thank god, these new js heavy frontends really hammer the performance of browsers and are often buggy.

[pjmlp]

Given that the browser should be about interactive documents, that is how it should be.