Becuase most of the contributor in the Ripple network is owned by the Ripple company itself, that's all I need to conclude that Ripple is not decentralized. Then someone maybe claim it happen because ripple is forced to do it since the crypto community already have bad judgement to ripple and they can't gather the contributor from the community. But the actual thing is that the requirement to be network contributor in Ripple is too high, and that is the manipulation used by ripple to make their network stay centralized.