Its not antithetical to the Foss philosophy. Thus happens because Linus is a trusted figure, something he's absolutely earned. He didn't just buy control of some product, or get promoted to this position by a company. Many great open source projects have a BDFL. If people lose their trust in the projects BDFL, they fork the project.

Also, the kernel is really just one part of Linux. Distros include a whole bunch of software they choose to deliver a full OS (hence the Gnu+Linux people). Linus doesn't have control over the OS as a whole, just the kernel.

Edit: Just finished reading the chain, what do you mean the dude did a 180? He expressed frustration that Linux only criticized him, further criticized the issues with the kernel development process, and said he was giving up being part of the kernel.