Yeah you probably could get more out of it. I wouldn't do so though. The uniqueness of the VVT, AFM lifters, etc, not letting particulates, wear metals, etc build up too much to be a detriment to those touchy components. I am a fan of taking things longer, but knowing about these technical issues, my comfort zone will not allow me to go beyond 6000 miles on my '15 Silverado. Same with our 2017 Equinox. I am not so paranoid about our '06 Cadillac CTS 3.6 so I tend to go a little further.I am running synthetic 5W30 in my '15 Silverado.
Going by GM's Oil Life System (OLS), I average 7300 miles between oil changes. I can probably get more but when the OLS gets down to 5% I change the oil.
I just reset the "trip 2" to zero and go with that. I really don't pay any attention to the OLM except to reset it when I change the oil.