Personally I think substantial changes are what merit designation as a new generation. There are significant technical differences between the 2014 - 2016 models and the 2017+ models. Though the changed beak is the most noticeable visual difference, along with perhaps the now black rear sub-frame, the biggest real difference is probably the addition of the Bosch IMU that enables the more advanced "lean sensitive" ABS. The 2014-2016 also don't have the "Combined Brake" system that applies some rear brake when the front brake pressure hits a certain threshold.
Whether or not those changes are enough to merit calling one a different generation over the other is debatable I suppose.
2018 V-Strom 1000XT
2011 V-Strom 650A (Sold)
"Remember, you don't really own anything you can't carry at a dead run."