The original claim was clearly actually just an opinion; I don't think there's merit to treating it as a series of logical statements, or at intricate depth in general.
Evidence for this is in the very words used: unnecessary, complex, bloated, convoluted. These are very human terms that are thus subject to personal interpretation and opinions.
It shouldn't be surprising then that their "claim" thus fails scrutiny. All they actually meant to say is that HTML and CSS are both verbose standards with a lot of particularities - still something subjective, but I think page / word / character counts are pretty agreeable attributes to estimate this with in an objective way. Hence why I brought those up exactly.
