>I tend to not actually read more than a 100-line markdown file

I tend to not actually read more than 100-lines of anything anymore. I've long referred to myself as "the Google generation": only being able to read the summaries in a search result. That, and the typical doomscrolling model of social media have affected my attention span. Reading anything more substantial takes real effort now.

Writing and editing html by hand is very simple, it can be just a few basic tags.

>But HTML documents are much easier to read, [than markdown]

Presumably you mean rendered HTML rather than the source documents?