I think it can be, it's just nobody does it. I don't know what formulas get compiled to though - I would guess PNGs, at which point you lose the benefits over a PDF (at least for equations). With proper browser support for MathML it could always be MathML though, which would render sharp and be readable by a screen reader.
It is unfortunate that MathML is not easily hand-written like the rest of HTML. What I find interesting in the link you posted though is that they embed the Latex or StarMath representation inside the MathML. It should be possible have tooling in text editors such that you only edit that Latex representation and on save the MathML representation is updated automatically.
It is unfortunate that MathML is not easily hand-written like the rest of HTML. What I find interesting in the link you posted though is that they embed the Latex or StarMath representation inside the MathML. It should be possible have tooling in text editors such that you only edit that Latex representation and on save the MathML representation is updated automatically.