Re: "the system has a more modern and 'flatter' look"
"Same reason Linux took off and BSD not so much. Because LibQT was open sourced just a bit too late."
Nah. LibQT became an important part of the equation many years after Linux blew past BSD in the number of developers and/or users column. The real reason is because AT&T's lawyers had issues with BSD. Linux was seen as being unencumbered with perceived AT&T license problems. We needed a cheap-or-free *nix for work, home, and play ... Minix wasn't it (yet ... it's a good general purpose OS now, check it out!), Coherent was about to go away (open sourced in 2005, find it at tuhs), the other commercial offerings were either brain-dead or stupid-expensive for home/student use. So Linux+GNU won by default.
That was the mid-90s; the rest, as they say, is history.
Note that I'm not anti-BSD, far from it ... I've used BSD since roughly the same time that ken got to Berkeley. It's a great OS, and IMO a better server OS than Linux ... although Linux is breathing down BSD's neck in that department.