Except if you want the ergonomics and low cost, you go for the crop sensor DSLR. There are still a lot of people in that category. The excellent 80D is still only about half the cost of this new mirrorless camera and it will certainly have it beat in many areas. Don't forget, the difference in quality between full frame and crop is noticeable only under limited circumstances. Daylight shooting, impossible to tell the difference. With each generation of sensor that difference narrows. Bodies like the SL2 show that it is possible to make small and low cost in a DSLR as well. Not as small as an M, but certainly small enough for many people.
And, that's not even considering specialty crop frame bodies like the 7D, which are likely to continue to find a niche market for many years to come.