It’s strange because it… isn’t really a joke, just wrong information? It’s not a high enough value to be obvious hyperbole (“I saved like a million on groceries”), so it looks like a typo that you didn’t realize you made and are now aggressively defending like you meant it as a joke. Not saying that’s the case, but that’s sure what it looks like.
Could you estimate how much it actually might have saved you? I think that’d be very good for the discussion.