Comment by jillesvangurp

Things like XML and XSLT were useful and nice when I used them in 2004. But that's more than 20 years ago now. It's not something I encounter regularly in modern tech stacks. How widely used is this stuff in browsers at this point? I don't think browsers should be burdened with a lot of complex solutions to serve a few minority/niche use cases.

And even then, using this stuff server side was more common than relying on browsers. XHTML was still being actively pushed and Whatwg kind of made that go away in favor of HTML5. Whatwg was a breadth of fresh air in the whole captial S and lower case s semantic web debates between XML purists on one hand and people just trying to create browsers that worked on the other hand. The latter camp won by virtue of eventually producing browsers that implemented Whatwg standards and then world+dog voting with their feet and making use of those browsers and standards. The whole debate just fizzled out after that.

XSL support in browsers is part of some of the reasons WhatWG was created: a lot of poorly thought through and half specified features being proposed by and rushed through the W3C. Which was putting browser makers on the spot having to support all that in a way that worked well across browsers. The job of "lets just sit down and specify this stuff properly" is why Whatwg was created. That's a job that took many years and it created the modern web and finally enabled high levels of interoperability between browsers.

And there are other mechanisms available to developers that are well endorsed by browser makers and standards. Including using whatever libraries you want in WASM form and running them in a sandboxed environment in a browser. Which is also complex of course but at least is being widely used and well specified at this point. I don't see many compelling reasons for this stuff to live outside of that sandbox.