Are you asking someone to change the markup on that page or having Translate extension work with less mark-up?

Currently I'm not asking for anything. I just wanted to express my feeling that the markup is hard to read.
It's not clear to me if the Extension:Math page is a negative example, because people added translate tag by hand, or if there was a tool that did that?
Furthermore, I'd be interested to see a positive example, how the translation can work while less ane more resaonable markup.
In general I have the feeling that translation on a sentence level works well for user interface elements or templates, but maybe not for long page text.
But I'm neither an expert in manual nor in machine translation.

Translate's page translation feature is oriented toward paragraph sized units. There are examples in the documentation.

I don't think anybody likes the mark-up, but it is necessary evil with the current implementation. For discussion about how it could work in future please see T50891 and T55974.

Phabricator is for tracking tasks, but there is no clear request here. What do you think I should do with this report?

There were several no-op tags, was that the issue?

The main issue of this page is that it's greatly unpolished by itself, see e.g. all the HTML comments and the inconsistent formatting of code snippets. If that was solved, there would be better chances to use tvar for inline snippets and less need for surgical marking.

@Nikerabbit: Thank you for the link to the the other tasks. I wonder, if there is a "replace HTML T commens with diff logic" bug as well.
@Nemo_bis removed the tags that do not have a function. Thus the bug is solved.

I don't want to blame anyone who contributed the the Math extension page.