Also I dont want to get the 80D because I don't think it is as cool as the 6D, all the vloggers on youtube use it and hearing that is a good vlogging camera makes me cringe. Well thats my opinion but that takes the 80D out of the picture for me haha.
The reason for this is two-fold...
(1) the vlogger could use a webcam ... but the image quality (due to lenses and sensor size) isn't as good. They prefer a camera with interchangeable lenses (like a DSLR) where they can select something that offers a nicer image quality. However, most DSLRs -- while capable of shooting video -- do not do a good job of continuously auto-focusing in video mode. This is because most DSLRs rely on "phase detect" auto-focus sensors located on the floor of the camera. When the reflex mirror is down (shutter is closed) the mirror bounces light down into these sensors which can focus
much faster then most other focus systems. But when the shutter is "open" and the mirror is raised clear of the sensor (as it would be during a video), it can't use those sensors and has to use something called "contrast detection" AF instead. This system isn't nearly as fast and it requires that the camera make several "guesses" to refine focus. You'll see the camera (during a video) do an annoying thing called "focus hunt".
(2) the 80D has a feature called "Dual-Pixel CMOS AF" (the 6D doesn't have this feature). The feature is especially useful during live-view. Canon found a way to integrate the sort of technology used by phase-detect AF sensors into the actual imaging sensor itself. This gives them the speed and accuracy of phase-detect AF, but they can actually use this during video. This allows the camera to focus continuously during video and the focus is much faster and follows the subject much better (you don't get "focus hunt" issues as the camera makes guesses as to how to refine focus.)
There were a few Canon models that experimented with earlier versions of the dual-pixel CMOS AF system, but with each iteration the system has gotten better. The 80D has one of the most recent implementations and it's pretty good. The 6D doesn't have this feature at all.
Canon's newest cameras have it. The feature is now found in the 1D Mark II (Canon's flagship DSLR), the 5D Mark IV, the 7D Mark II, as well as the 70D and 80D. The newer Rebel series cameras have something called "Hybrid CMOS AF" which is an older implementation that works pretty well (much better than contrast detect AF) but not quite as good as the dual-pixel CMOS AF system.
So basically if the vlogger buys an 80D, they get a camera optimized for video (it's about as close as you can get with to just buying a dedicated movie camera -- but with the interchangeable lens capabilities of the DSLR). This makes the 80D one of the most popular DSLRs on the market for those who are primarily interested in the video features.
The 80D certainly has a better AF system then the 6D.
Though sensor resolutions are similar, the 80D has a tighter pixel density (the 6D spreads the pixels out over a 36mm x 24mm area whereas the 80D fits them into the smaller ~23mm x 15mm area.)
The other thing to consider is that the 80D is a newer generation sensor and it's quite an improvement. So while it's technically an APS-C sensor, it actually does outperform the 6D on low noise at high ISO and dynamic range. The 6D has been out quite a few years and the rumor speculation is that there may be a replacement 6D (e.g. 6D II out ... probably within a year, but who knows.)