My intent was to put forth what it is describing, which is to allow the user to request the erasure of their information and subsequently that provider should then take reasonable steps to do so.
If that provider, chooses to keep content creators information more central to itself and not allow it to be as widely spread. Then that's more power to the curator and could be something that Quora wants to uphold.
On the same token, just because something has been posted on the internet doesn't mean that the provider of such content is obligated to spread it as far and wide as they want. They are allowed, to take efforts to restrict is movement.
You can certainly take efforts to restrict its movement, as Quora has done here. It's mostly futile, though, especially in this case. Archive.org might not be willing to save it, but I guarantee plenty of comparable services are.
If you post something to the internet, it's permanent. Lawmakers can say all they want, but someone somewhere is storing it regardless of laws, and it can get out again at any time. From a security perspective, it's irresponsible to provide people with the illusion that they can erase their tracks; they'll believe they can truly eliminate all trace of what they said and prevent any future consequences when that's clearly not the case.