In many situations both players will have marginal hands with a very high frequency => your strategy is only good if you have not put much money into the pot to begin with. What you are advocating is 3betting a very narrow range and calling 3bets with a very narrow range.. As I hope you can see this leads to a very poor strategy.. What you need is a better understanding of position.
I don't understand where you are getting this from. When you have a lot of fold equity you can always resteal, but the idea is to give up spots where at best case scenario, according to your own ability to play poker, the result is breakeven. From early positon only having value oriented opening ranges unless we are specifically isolating a player from the blinds and the table allows us to do so. Late position however we can minraise/fold buttons for example and don't have to worry about playing back vs 3bets. We can for example, tighten our opening range vs players who stop folding... If they players call X % of the time, but fold enough pre to make our open +EV in a vacuum, we are freerolling the times we flop the nuts vs his continuing range and he spews into us. I use this kind of logic pre flop and on the flop very often, when my hands are marginal, but there's some small edge pre flop and profitable opportunities later on (if our opponent folds A LOT we will steal with a cbet, if not, we don't start fighting over a questionable edge, because we have to beat rake etc and can make mistakes ourselves).
We invest X amount of BB-s with a profitable plan in mind (it can be as simple as the EV of our own action in a vacuum, and if it's +EV, we can stop the hand after that if we don't like the future). Post flop again, only take good spots as they get more complex, avoid big mistakes by managing the pot size well with questionable hands, if you can't come up with a plan, you could bet/fold X% of the time to break even vs opponents folding frequency (you are choosing your odds on a bluff).
I really don't like spots WHEN i am not targeting a specific leak of my opponent and I'm forcing myself to call or fold, it's something I completely try to avoid (again, when I'm not targeting a specific leak) and pre flop my choice becomes raise or fold if 3bet is +ev in a vacuum or for example, if my opponent calls 3bets and folds enough to cbets to make that plan +EV. If not, I might just choose folding pre. Post flop if I'm out of position, my options become betfolding or checkfolding in most cases, vs aggressive opponents who bet fold, I may choose to checkraise, based on just the odds. Again, no plan - I'm giving up. With marginal hands after these actions when I considered them +EV in a vacuum, I say I can safely check fold. And when I have huge equity advantage vs my opponents continuing range, I can easily get value. Now if my opponents call me a lot, I punish them by doing it for value only, and if my opponents fold a lot, I slowplay to extract value that way (underrep my hand and they perceive my continuing range to wider still, because they don't know I'm polarizing my calling range to hands that I beat his valuebetting range (this is when I don't have a reason to bluffcatch (if I can't bluffcatch, I can check/fold or bet/fold if opp folds X% of the time - very effective for donkbetting for ex. [these are examples "plans", ofc I have many more complex and very opponent specific types aswell]).
To sum it up... We can end the hand with a bet, when we don't have a reasonably profitable "plan" & we can squeeze out some immediate profit. And if not, we c/f, because we were profitable up until that point.
*Reasonably profitable = We know where we stand in the hand and how it will play out without us making mistakes (we know where our profit is coming from, we have it defined) & we are showing X amount of profit.
This is getting long... but I hope you understand how my though process is by now.