That may be true (we don't really know for sure) but the point is that the camera can do sports with pixel density for reach and good fps.
If you are referring to professional sports shooters then there would be very few in my opinion but the stereotypical "soccer mum" would think that it is a good camera for action.
I really noticed the difference going from my 7D to 5Diii for indoor sports but I wouldn't have thought about using the M6ii as a replacement. My R5 is a dream now
I had pretty much given up on using my 7D for sports in artificial light due to the poor AF performance in low light as well as the amount of noise in the files. I was using my 5D Mark III with my 70-200/2.8 and my older 5D Mark II with my wider lens (usually a 24-105/4). I too noticed a significant difference 7D → 5DIII in terms of both hit rate and image quality. I still used the 7D for daylight sports where the difference in reach was greater than the difference in noise/AF in good light.
Then the 7D Mark II came out. I had absolutely no plan to ever buy another APS-C body again. Until I saw that it had flicker reduction.
The flicker reduction provided by the 7D Mark II was worth more to me than the better S/N ratio of the 5D III if both are used in the exact same point in the cycle of the light's flicker. The 7D Mark II shutter is always fired at the peak of the light cycle and the 5DIII shutter is not. The light falling on the front of the lens can be a stop or more brighter, as well as fuller spectrum, at peak than when the light is in the bottom of the trough. With the APS-C camera always firing at the peak and the FF 5DIII a crap shoot that often shifted color/brightness from one side of the sensor to the other or hit the very dark bottom of the trough, the S/N ratio difference was moot. My hit rate went way up and my post processing time went way down because the color was much more consistent from frame to frame as well as from one side of each frame to the other. The 7D Mark II AF is also almost as good as the 5DIII AF even at HS stadium light levels.
So I switched back to using the 7D Mark II with the longer lens and the 5DIII (and then 5DIV) with my wider lens when shooting sports under lights. I'm now using a Sigma 120-300/2.8 with the 7D Mark II and the 70-200/2.8 with the 5D IV. Depending on the weather forecast, I'll put either a 24-70/2.8L (original) if it's going to be dry or 24-105/4L IS (original) if it might get wet on the 5DIII.
That 120-300/2.8 is heavier than a beginner's eight pound bowling ball, though. I'm debating selling it and going back to just cropping the stink out of the 7D II + 70-200/2.8 and only carrying two bodies for field sports. I really need the wider angle for the work I do at halftime with the bands, and it's far too swampy here in the south during all but the end of the season to make me comfortable with changing lenses at the beginning and then again at the end of halftime.