Hi,
The goal of any escaping here isn’t to prevent your content from being treated as markdown, but to prevent pasted HTML being treated as HTML (which markdown supports).
In this case at least, Deepdwn is returning the HTML text content as is from that source, rather than doing any escaping of its own.
For instance, the author of that content didn’t need to HTML escape any of those characters, other than the <, but they did anyway, and Deepdwn happily passed them along.
Markdown’s HTML handling is less strict and would allow < in some circumstances, but not others.
“[n]<word” would be allowed but “[n]<word > something” needs escaping on the opening “<”, or else “<word >” will be treated as HTML and dropped or escaped, depending on your markdown conversion.
I’ll see if there’s anything I can do to improve it, but there’s a good chance that you’d still see some escaping where you wouldn’t necessarily want it, in which case Paste as Plain Text is still the best answer.