wall of text

I'd just like to note for the record that your post wasn't a wall of text. Not only does it have paragraphs, it is also well-structured in its information delivery and you use connectives well, constantly answering "why am I reading this sentence (or subordinate clause)" in the first couple of words. This is not only easy to do (if you're used to it), it also takes enormous load off the reader by not having them divine erm "train of thought context", and actually follows natural speech patterns. But it does require that your thoughts are organised, that you can write the whole thing in one go, or you will have to go back and massage everything down to size. Which brings me to

TL;DR

"I didn't have time to write a short letter, so I wrote a long one instead".

Or, differently put: Writing skills are actually just as if not even more atrocious across the board. Another reason for tl;drs are people who are paid by word count.