All tackles when the ball has gone are late, when the tackle occurs the first thing he has to decide is was it late yes or no, if yes he will then decide could the player tackling have pulled out, yes or no, if he didn't pull out did he try to pull out, if contact was made through not pulling out was it forceful or was it glancing (due to trying to pull out), did late contact impede the kicker from following the kick. The ref makes all this analysis in a split second, it really is that simple
If every late touch on a player was given as a penalty this board would enter meltdown.