From a biological perspective, we benefit from diversity. In fact, humans are here largely because our distant evolutionary ancestors developed differences from their peers that caused them to be able to survive better.
I think this is true in sociological terms as well. Societies, I believe, are enriched by diversity of thought, backgrounds, and beliefs. It makes them better able to withstand change or other situations beyond their control. Economies are stronger when contributions are made by diverse sources.
In this sense, we should prize members of society who are different. We should be open to them and learn from them. I understand that reality is often different. We tend to shun "the other." Strangely, this seems to be anthropologically-rooted desire to stick with our "tribe." It goes against what we know from other sciences, though. The only way for humans to overcome this is for us to be proud of our differences and open about them. This is where I believe the notion of "be yourself" originates. We can take pride in being different. Not to be overly dramatic, but the future of our society and species may actually depend on it.
I think that too much difference in the context of modern day society could also have a sort of centrifugal and fragmenting social effect, as unfortunately the tribal mentality is still very much a dominant feature of human nature. We evolved from small uniform hominid communities, and modern day societies with sprawling urban area and vast populated alienating spaces are diametrically opposed to our genetically determined need to belong to smaller groups operating within restricted areas to play a meaningful part in them. So maybe difference itself isn't the main issue, it's actually the way modern societies are configurated, which creates existential voids and alienating environments for people, whose only outlets when they aren't working a menial unfulfilling job are to consume the latest ephemeral gadgets and shows or ingest copious amounts of alcohol or drugs. Many people don't feel they 'belong' anywhere anymore, they feel divorced and disconnected from any kind of meaningful locality, which is a function of the way modern societies and economies have evolved and grown, in ever increasing outward circles which overlap with others to create a globalized system of commerce and capital flow. This is what I would call the globalization paradox, that the more the world becomes an integrated global village linked by telecommunications and multinationals, the less the majority of ordinary citizens of such a global community feel that they belong anywhere or have any meaningful role to play, the effect of which is alienation and disconnection from the world itself.
In this context, some people may experience 'difference' and 'diversity' policies and agendas as ways to further fragment and divide an already vastly dilated, nonintegrating and hostile socioeconomic order, hence the recent rise in nationalism and rejection of/hostility towards supranational entities like the EU and UN or global finance and banking organizations which pretty much amount to transnational virtual senates with no democratic accountability.
As an interesting sidenote, look at the oldest continuous civilization, China, which has always been quite uniform and homogeneous (although modern day social-credit system china isn't exactly a haven of freedom and tolerance).
Saying all that, I still agree with the spirit of your post.
Also, I've just remembered that the original thread is about 'being yourself', so apologies if this veered too much off topic.
