There are many reasons people hide what they identify with so that they are more accepted.
Growing up is often a process of learning to lie as our parents and teachers tell us what is appropriate to say or do or not, especially in public. We thus learn to mask as our modus operandi. As we mingle with our peers, we find there are things we can do and things we can't if we are to belong to their group. We are building up quite a repertoire of scripts that become our public persona into our adult life.
For those with neurological conditions, such as autism, fitting in is a difficult process as what others may get easily does not make sense to them. For them, social cues are missed and so they study how other people act in some situations and try to mimic them. Other situations they will stay clear of because they just cannot cope. Often they haven't been diagnosed with such conditions, but the general pressure to conform, coupled with reactions verging on hostile to some of their behaviours makes them not want to find out as it would lead to more stigmatism. Masking is for social survival.
For others, coming from a country with a different culture and language can be daunting as they can face prejudices and even violence. They will try to adapt their public speech, actions and appearance to be more acceptable to those around them.
Those in these two groups can feel like they can't really be themselves as they have to mask those characteristics that others find disturbing or annoying in order to fit in. While we all mask to some extent, it is stressful to be constantly having to keep on top of how we might be coming across. The public persona just seems too alien to the identity we know of ourselves.
However, there is a significant difference in the two groups. While it may be difficult to break out of our cultural influences, they are there because we accepted and have grown attached to them as part of our identity. But we can decide to change our cultural identity and adapt. That is not something that those with neurological conditions can do. Of course, the more we accept our lives as they are, the better we can do something about those aspects of our lives that are not defined by our biological limitations, but it is that those around us don't want to accept us as we are that is the problem.
We would be better off if we could just accept people as they are, but we live in the world we have, so we can chip away at prejudices to allow more freedom to be who we want to be. That is what we as societies need to work towards, but when we work out what to compromise on, those who cannot change, as opposed to those don't want to, must be the priority. We cannot force those who cannot change to be what they are not, and it would be totally unfair to try to. To bring them social acceptance would open the door to wider acceptance of differences in culture and outlook .
Celebrating cultural differences is what marks a truly multicultural society, but that does not mean that all aspects of a culture must be accepted, especially if they embed prejudices against other groups or even those within their own culture. Respect and freedom must be universal, and culture should not be seen as a defense for discrimination. Modern democracies are the result of progressive and deliberate actions to prevent discrimination against groups within them, and no amount of cultural history should be allowed to forestall equality.