This is mostly, not 100%, but largely, nonsense.
First, no one suggests defense is based solely on effort, but its mostly based on effort. Back checking aggressively doesn't require some magical sense that only the rare few possess, it just takes determination. Blocking shots doesn't take some skill that only Bergeron has, it takes guts. Next, EVERY NHL player understands the basics of the game without the puck. There is of course varying degrees of anticipation, but that isn't what you claimed. You stated some people get the basics and some don't, which is mostly baloney. Of course there are varying levels of skill in terms of anticipation, positioning, reaction time, without the puck, but again this isn't what you claimed. You claim its some absolute gift which any player either has or doesn't have, simple nonsense.
It can be developed, it can be practiced, it can be improved. Bergeron didn't come out of the womb with great defensive instincts and effort, he worked at those things.
But the simplest, easiest thing most players can do to improve their defense is to simply try harder at it. There's nothing silly about this concept. Cup winning teams give defensive effort much much greater than their own regular season defensive effort - We saw this personally with our Cup win, Ovi blocking shots, Backie blocking shots, everyone committing to the backcheck. Its actually silly to suggest that better effort would not lead to better defensive results, we see this in our own team all the time, withing a game, within a season.