tbf, I agree with various points he made. The backrow does need to have balance, which hasn't been there. A 7 shouldn't just be focused solely on breakdown.
I just think he's created a bit of a straw man by saying that 7s follow the breakdown behind the defensive line.
At least, Kvesic doesn't do this. Kvesic gets in a position in the defensive line that maximises his chances that the next carry from the opposition will result in a turnover. Which usually means standing about 3ish players down the openside defensive line. Stand too tight to the breakdown and the opposition simply floods the carrier with supporting players. Doesn't matter how often the opposition do this; you're only going to get scraps when contesting. Stand too far away from the breakdown and it's too unpredictable where the ball will end up. There's a sweet spot, a pass away from the current breakdown, where forwards regularly take it into contact, and Kvesic tries to occupy a space in the defensive line around there. He can also operate on breakdowns either side of him, giving a good area to cover. Results in a lot of tackles, and a lot of breakdowns to contest, without chasing the field for them.