Dave Gerard’s comment on Foundation-L neatly encapsulates the problem with Wikimedia’s actions and with the defences of them that I have seen so far, stating of the artists -
They’re performance artists. This is more performance. They fooled the EFF into playing along.
The problem is that people’s first amendment free speech rights are being dismissed because they are artists.
The EFF wouldn’t have had to “play along” if Wikimedia hadn’t decided, despite the history of first amendment protection for non-commercial, critical and artistic use of trademarks by artists, that art is less deserving of protection as free speech than simple verbal abuse would be.