Zouk, the issue is insignificant so long as your black focus point is across a light area as in your posted sample. Though red is quicker to work with as it's THERE and you don't have to go looking for it. But when that selected focus point goes across a dark area ie dark stage area, a dark or black suit or dress, a dark stadium background...there are a bazillion examples. Think about it. Black on black is hard or impossible to see.
It's a non argument. Period. Respected photographers are speaking up. Chuck Westfall from Canon USA acknowledges the issue. It's real.
Makes sense. I'll count myself thankful that I don't have to shoot in sports venues that dim.
They made a switch from the reflex LED AF points to the front-lit LCD AF points for one reason or another. Let's hope it's a reversible design decision; if it can't be reversed, hopefully we'll see a change in the next generation.