To be completely fair, looking over the lines removed by the PR, there don't appear to be any normative statements requiring HTML handling XSLT unless I missed one.
I get that people are more reacting to the prospect of browsers removing existing support, but I was pretty surprised by how short the PR was. I assumed it was more intertwined.
Their explicit intent is to generally remove XSLT from browsers.
If this was just about, e.g., organizing web standards docs for better separation of concerns, I think a lot of people would be reacting to it quite differently.
I get that people are more reacting to the prospect of browsers removing existing support, but I was pretty surprised by how short the PR was. I assumed it was more intertwined.