I actually don't think that it is. And I know that I'm arguing up the middle against two sides that are arguing against each other right now, but there can be ignorant extremism on both sides of this issue.
It's unfair and rather sad to assume that white people cannot understand that diversity is important to a racialized person. I like to believe I can understand something like that as true, to riff off my point above, and to incorporate that truth into a framework of advice, information, etc. But that's not what you are quoting.
It's completely fair to state that white people cannot understand why diversity is important to a racialized person. As in, understanding the qualities of the background and experiences that have created that value and led to it. I mean, come on. That's true of so many things and so many experiences. If someone has gone hungry in the past and now insists on keeping the fridge full at all times, I can understand that the feeling is true but I can't fully understand why it's true. It's simply a part of someone else's life experiences that I don't share.
This topic is stupid, and apparently was conceived as such. But despite having my own back up, I don't want to pile stupidity on more stupidity. It's not going to cancel itself out. It just multiplies into more stupidity.