An attack on XRP is not an attack on any crypto, XRP is not a cryptocurrency.
Cryptocurrency doesn't really have any value here since it is not a definitional term that is relevant from a regulatory point of view. this is relevant for the whole industry because it will evoke a definition of "security" as to be applied to the crypto sector. If XRP gets classified as a security then a lot of other cryptos will be as well.
Check out Chris Hoskinson's latest videos on the topic. He is saying the same thing. People saying that this is a good day for crypto do not grasp the significance of this event.