You'd have a point if the quote in question was a long prose quotation. It isn't; it's a poem and code formatting is often the only way to get poetry to appear reasonable.
Code formatting does not get poetry to appear reasonable. That's actually the whole issue being discussed.
On the other hand if you don't like each line spaced as a paragraph, as it would be if you try to keep the line structure I. HN non-code text, you can, on HN, use the same convention used everywhere else that it is impossible, impractical, or undesirable to set poetry while preserving the line structure:
“this is a line of poetry / and this is another line / each separated from the next with / a solidus set with space / on either side.”
HN quotes are fine on mobile. But, just to be clear, this is how HN does quotes:
“quoted text”
And this is how HN does code blocks
HN code blocks abused for long prose quotations suck on mobile (and aren't appealing on desktop, either), but that's abusing code blocks.