Santa Claus is part of the Christmas tradition. There are religious elements to the tradition and there are secular elements to the tradition, but they all work together to add meaning and festivity to the celebration of this holiday. There have always been critics of various aspects of the holiday, but for some reason it has in recent years become extremely fashionable to find fault with traditional ways of celebrating Christmas. There are different angles taken by different groups, but there seems to almost be a competition to find something to complain about, no matter how trivial or inconsequential it might be. It's probably best to just see this as an example of virtue signaling. Whereas some people virtue signal by going to extremes in the way they celebrate Christmas (for instance, putting up extravagant light displays), others virtue signal by posting tirades about how the holiday oppresses members of marginalized groups. Meanwhile, normal people just roll their eyes and go about their business.