At least in my opinion, the ThinkPad Carbon X1 is glaringly missing in that lineup.
"No USB-C ports. No Thunderbolt 3 ports. Too many video out ports. Unnecessary SD slot. 6th generation CPU."
Why would you want or need either of these for a Windows/Linux machine? USB-C is near non-existant and the Carbon uses the Lenovo flat connector for charging. Instead you get 3 USB3.0 ports.
> Too many video out ports
Who cares? They aren't taking up space. You get HDMI for easy connecting to a TV without any adapters and a mini-displayport for everything else. Seems like a win-win to me. HDMI is the most common and near universal video connector now. The lack of HDMI on Apple laptops is inexcusable.
> Unnecessary SD slot
Uh, another who cares. Hell, put a second OS on there for kicks, load up photos from your mom's old camera, run a hypervisor on it and use local storage for your VM's, etc.
> 6th generation CPU.
The i7 model has a i7-6500U from Q3 2015. Its fairly newish and a great performer considering its energy use. The current X1 is in its 4th generation and from early this year, so of course it has a late 2015 processor. More than likely you'll see a 5th generation early next year if getting the newest processor is important to you. Not that intel's yearly offerings differ too greatly from last year's model.
True, though with it being featured in the Google Pixel, I'm certain it'll become more common.