Eh...I would be willing to bet that a majority of the people who upgraded or purchased the 2018 model were hold-outs from the 2015 or earlier crowd. Anyone who upgraded from the 2016 or 2017 model did so solely for the increase in RAM and cores.
Once you make it outside of this forum, you realize that 95% of the world doesn't really care about anything other than what it can do, and how fast it can do it. Until the 2018 model came out, there was very little reason to upgrade for processing power alone - it was stagnant. If you need proof of that, go check some GeekBench scores from 2013 through 2017 - they're marginal at best. The introduction and release of hexacore processors has resulted in the largest increase in performance that we have seen in a long, long time.