I think the description of "blockquote" https://cs.stackexchange.com/editing-help#simple-blockquotes is confusing. It doesn't explain what blockquote should be used for and instead says
You don't need to hard-wrap the paragraphs in your blockquotes, but it looks much nicer if you do
which makes it sound like something we should use for paragraphs (e.g. it happens here).