Earlier quoted context omitted.
Politics. "But politics shouldn't be a factor in software design. We should cooperate to work with the technologically most useful solution and not let personal or ideological differences get in the way." Bless your heart.
That's one of the critics of open source (BSD) world versus free software world. GNU /Linux projects have been designed for figthing on socio-ethico-political grounds against proprietary software. The first one being Unix. (GNU's Not Unix) On the other hand, BSD prefers to see itself like a community of pragmatism, and creating values in business by sharing externalities (plus a bunch of fanatics that loves nice code…
The reason the Linux community is so dysfunctional is because, for most people born during a certain time period, it's the first ever OS they use that isn't Windows, and the first ever Unix. Naturally this creates a lot of sudden revelations, and a lot of blowhards who think they're hot because they can rice their Arch Linux box. In the process a lot of false sense of technical prowess is generated.
Moreover, the network effects become so strong that at some point (which has already been crossed) Linux becomes the alternative OS, and from then on people feel like they can just ignore everyone else with impunity. They start to perceive themselves as the leaders, and everyone else must be biting their dust. Notice how Linux users often tend to be ignorant (and not only that, but resentful) of what BSD, Solaris, MINIX, Hurd and other folks are doing. Not the case with users of those other OSes, who as underdogs have more of a reason to cooperate and usually also have to study what the other is doing, especially so that Linux the big dog doesn't poorly reinvent some interface that ends up mutating across FOSS and leaving their access to portable software in the dust.
If through some historical accident 386BSD ended up making it unfettered from the trademark lawsuit fallout, it likely would have followed the same course. So would have the Hurd.