Please ignore that (3rd) idiot sandwich. Same as Hu Xijin, this Zhao guy does not speak for the Chinese government.
Therefore, his words should be discarded as rubbish.
Sure, the so-called "peace plan" can be very useful - or it can be utterly useless - depending on the present development in Ukraine, and based on which side one is standing on.
On the other hand, I believe we can see this so-called "peace plan" from another angle, i.e. Beijing extending her hand out to the West, Ukraine and Russia, as a signalling that China is willing to play a part in resolving the war in Ukraine, no matter how big or small that would be.
Whether they want to shake China's hand or not - Well, that's another matter entirely. And we have already seen the result - Russia shakes China's hand with a willingness of 70-80%, Ukraine more like 10-20%, while the West is practically 0%, i.e. slapping China's hand away.
Furthermore, remember that Von der Lying of EU outright rejected China's proposal merely based on the fact tha China has chummy relations with Russia. Jens Stolenburger of NATO even went as far as claiming China as unreliable. So what's there for China to talk about with the West on the resolution of conflict in Ukraine?
Perhaps Beijing is already expecting such responses from the West from the very beginning - Just the clauses #2, #3 and #10 are absolutely unacceptable to the West. Why? That's because the West is already planning for this conflict to happen since 2014. Nobody in Washington DC and Brussels would like to see an outsider stepping in and end their good war business with the flick of a switch.
However, in the eyes of the rest of the world, Beijing's actions of proposing this "peace plan" is already seen as a gesture of 伸出橄榄枝 (offering an olive branch), such that at the very least, China is already offering the possibility for all sides involved in the conflict to sit down and talk. The rest of the world will see China as a responsible power, who actually does try to kickstart even tiny bits of efforts that hopefully could lead to the restoring of peace in Ukraine.
On the other hand, since it is glaringly evident that the West would not even consider China's proposals at all, this shows the rest of the world that the West is the true instigator and pusher of war and destruction in Ukraine. In the end, China is not the one suffering from bad optics here - the West is.
In fact, this could very well be a trap set by China - and the West walked right into it. Perhaps this could also be the switch in Beijing that "See? Since the West is unwilling to work for peace in Ukraine, and wants to increase intensity of conflict and duration of war, therefore we shall begin preparations to provide more necessary aid to Russia. As long as NATO is tied to Europe, we would have greater space to breathe and be prepared for the eventual showdown over Taiwan."
To sum it up, this proposal - Combined with the "US Hegemony and Its Perils" article released by MOFA China just several days before the release of the proposal, and the news of Wang Yi's (and future Xi's) visit to Moscow - I think the message couldn't be clearer: Beijing is now dead-set on working to break up with DC and Brussels.