While yes, that is true, it doesn't necessarily apply to this circumstance. The person you replied to might have played a song by an artist that was an inferior copy uploaded by another user.
We restrict uploads to a minimum of 128kbps and prefer 192kbps if it's available. It is of course possible for someone to transcode a 64kbps file up to 128 or 192kbps to make us play something that truly sounds awful, but based on my own personal listening that doesn't seem to be the case often, if ever, in practice.
