I agree with most of what he says, especially about providing decent tools for (remotely) managing and "locking down" large numbers of desktops.
Linux desktops are ideal for many businesses, where very often a web browser and perhaps word processor are the sum total of application requirements.
Unfortunately it feels like the focus in the past few years has been on making things look pretty rather than making them convenient to manage; things have got worse for simultaneous, multiple user systems rather than better, as application developers largely fail to consider anything other than traditional single-user PC scenarios.
The idea of providing tools to easily centrally configure and consistently lock things down might grate on the nerves of a "freedom is everything" purist, but in the real world it's basically essential in many business environments, and sadly not something that any current open source desktops do well. I'd be happy to be proved wrong of course...