The phrasing was weird, but this guy was born in Egypt and the statue was taken from Egypt. This isn't a matter of private property, he's commenting on how the UK exploited Egypt.

Sure, race and nationality are social constructs and genetics don't support the divisions we make along phenotypic lines, however, you can't just hope to solve racism and colonialism by saying they are gone and meaningless. If you say they no longer exist, that doesn't erase the impacts racism and colonialism have had on a people.

In essence, it's like punching someone repeatedly until they are bloody, stealing the money from their wallet to buy yourself a house, and then saying, "why can't we forget our differences and just be friends?" Is everything alright? Is it ok that you now have a home and the other person is destitute because you stole their money? Does it make it any better if it was your parents or grandparents who did this and now you've inherited the house?

Just claiming it's a social construct and wiping your hands of the issue does not fix the problem. And that metaphor I made does not even encompass the entire issue! Reality is more along the lines of: now that you own this house, you enforce policies that continually raise the price of housing and put a tax on people who don't own a house. The exploitation many people have suffered at the hands of racism and colonialism never stopped, it just changed it's form.