good question, hope someone can answer. Curios too

So yeah, I want to know why it's the higher EV play.

Imo it is not higher EV(maybe very tiny bit on some textures), we can use many different sizings as flop cbet strategy and have ''same EV'' (though rake can change it, but I haven't worked on that and can't comment)

Not only for range advatange but people in general have a really poor defense vs small betsizings.

In a balanced model the 1/3 with strategy with range advantage pushes the most equity and captures most of the EV

What happens is you get to bet hands that otherwise are forced to check/fold allowing them to capture some of the equity while villain cant do much about it because of the range advantage. Leveraging your equity advantage so to speak

I think I get this concept now guys of pushing equity even OOP.

So, this works best in BB vs SB spot where BB has a very wide range that is forced to defend vs our 33% cbet and is easy to put a lot of pressure on turn with an overbet with our more polarized range. But in UTG vs HJ spot for example where the IP caller has much tighter range, even when we have an equity advantage, 33% cbet is not best since villain can defend this very easily, so we'd rather use a polarized cbet strat with bigger bet sizing to put pressure on his good hands on flop right away.

This also applies in SBvsBU spot for example where we have 3b linear range and BU has wide calling range.

Because they're using this strategy it only means it's the higher EV strat,

Not true at all. On certain textures and with certain pre-flop strategies range-bets can capture most of the EV of a full strategy but rarely will it capture all of the EV.

They use it because the players they are playing against are not responding correctly versus it (they should be Check/Raising or Raising more frequently and merged). If players respond correctly then range-bets are a horrible strategy in many scenarios.

but I don't want to blindly incorporate the strat in my game

Smart. Do the work yourself to find out which strategies are best in different scenarios and why.

It is a broad generalization to assume "range-bets" and "range advantage" go hand-in-hand. There are many factors that should go into every decision and with most anything in poker, "it depends".

Because this strategy is very easy to approach.actually in theory,some spots betting polar gain more ev,for ex:BTN vs BB AK3r,BTN need to bet very large with good Ax and a lot of pure air，improve range ev.But people defend this strategy easy,just call good hand and fold trash hand,but when BTN bet range small,BB need to defend more,but they don't,so BTN gain more ev .

Thanks for all the feedback guys

I now learned that it's not about which strat is higher EV but rather it's about simplifying our strat.