It's intentional. It stops the mindless quote pyramids of doom. Look on the bright side: Before, the quote tag (any tag, actually) broke after like the 3th or 5th level; now you can quote pyramid all you like, as long as you put in the effort to do it.

Besides. if people would just replay to the post they're replying to, you wouldn't need stupid quote tags for "conversation flow", because the flow would be evident.