One of the least attractive aspects of modern social justice activism is the criticism of actions as cultural appropriation. The basic idea is that the group or nationality or ethnicity who developed some practice should be the ones who are allowed to practice it. People outside of that group are not allowed to engage in the practice. When stated in this way, the idea seems absurd. It seems to suggest that white westerners cannot practice Yoga because it was developed in India. This Wikipedia article develops the idea in a more nuanced way, but the attempts at nuance do not eliminate the basic problems.
There is so much wrong with the idea that it is hard to know where to start. One obvious problem is that it is focused on group rights. Somehow a group is said to own a practice, even if the members of that group had no participation in its development. That people from India developed Yoga does not mean that people from that area today have any special claim to it. Another problem is that the people who developed the practice somehow have a claim to exclusively exercise it. But that is not true. If a person develops a practice, that person does not get an exclusive right to practice it.
Sure, it is possible that some of the things that are criticized as cultural appropriation are problematic. But it is not because it involves cultural appropriation. For example, if someone dressed up as a Hasidic Jew, with the various distinctive clothes and religious items, and did so in a way that indicated they were looking down on and making fun of those Jews, then that would be problematic. But not because they were culturally appropriating anything. The reason it would be problematic is that they would be making fun of a group. The cultural appropriation is irrelevant.
But the worst aspect of cultural appropriation is that it is inconsistent with the cultural development and enrichment that a free society promotes. In a free society, people from different cultures bring their practices to the wider society and they are followed by others in that society, making possible a richer and improved culture. To take just one example, consider the area of ballroom and Latin dancing. If one engages in this practice, one dances a variety of dances, including the Foxtrot, Tango, Waltz, Viennese Waltz, Salsa, Rumba, and many others. These dances originated in many different cultures, but no one regards dancing those various dances to be problematic. Instead, the combination of these dances from different cultures evidences “the creative powers of free civilizations”—and makes for a dance practice that exceeds what any one of these cultures could produce on their own. It is true that the people who engage in these dances may modify aspects of the dance practices to depart from the original form, but they do so to develop the form and to fit it into new circumstances. There is nothing wrong with that. In fact, these dances, like other cultural practices, developed over time to become what they are.
In the end, the criticisms about cultural appropriation turn out to be inconsistent with essential aspects of the greatness of a free society. These criticisms are an attempt to prevent people from the generally beneficial process of modifying and mixing cultural practices, all in the name of group rights.