To further your point. In our bodies we have organs which are made up of specific kinds of cells. In some cases diversity of cells seems to come with health benefits (e.g. our guts), but in most cases cause significant health issues. (If you have a bunch of liver cells in your lungs it's probably going to be a problem). Also across the whole body there is an incredible diversity of cells, and they cooperate with mind boggling harmony.

My take away is that diversity at a global level, and in some specific contexts, is a great thing. But diversity in some other specific contexts is entirely destructive and analogous to rot or decomposition.

When we rely on a core societal function (firefighting, accounting, waterworks maintenance, property rights, etc.) the people responsible for maintaining these functions need to maintain in themselves a set of core characteristics (values as patterns of action), and there is room to play outside of those cores, but those cores shouldn't be jeopardized as a tradeoff for diversity and inclusion.

For example, if constructive core values of a railroad system is consistency and reliability, then these shouldnt be diminished in the name of diversity and inclusion, but if diversity and inclusion can be achieved secondarily without a tradeoff (or even to somehow further amplify the core values) then it is constructive. One has to thoughtfully weigh the tradeoffs in each context, and ensure that the most important values in that context to maintain the relevant function are treated as most important. The universe seems to favor pragmatism over ideology, at least in the long run.

So in a company if the core values that make it successful are diluted in exchange for diversity, it's no longer what it was, and it might not be able to do keep doing what it did. That said, it also might have gained something else. One thing diversity tends to offer huge complex systems is stability, especially when its incorporated into other values and not held up singularily.

In other words, my take on diversity (and by extension, inclusion) is that we need a diversity of diversity. Sometimes a lot of diversity is best, and sometimes very little diversity is best.