I found a standard range online for the cutoff which is QJs and above plus pocket pairs. Even though there are hands in between 2's and QJs such as QTs. Is it valid for your range in any position to be the top x% of hands (dependant on position), are you losing equity by doing this?
Its easier to know when you're ahead playing pocket pairs vs QTs, which allows you to bet for value when you hit the board, or bluff/fold when youre behind. Imagine a KT2 rainbow flop with QTs. You wont get much value if youre ahead, you may be betting into a stronger hand, you're stuck with a bluffcatcher if facing aggression.
By including lower cards in your range, youre covered on more board textures. If you only play broadway cards, you basically miss every low board and have to check/fold.
As you have said: If you simulate one player with 100% range all in, to a second player with 100% of the range all in, then even QTo beats 22 for overall number of hands won. Infact this is true even for a 9 player game.
But if you compare top 50% of range all in, to top 50% of range all in, then QTo performs like garbage and is beaten by 22.
So you have to be careful with what logic you are using to construct a range. For example in a two player hand (ignoring blinds for a minute...) you should obviously open with top 50% of hands. But your callers logic will be to call with top 50% of hands. So therefore the equity of a hand is actually how well it does against the top 50% of hands. How well it does against the bottom 50% of hands is irrelevant.
QTo gains most of its equity by beating lower off-suit hands, which are in the bottom 50% of hands. Where as 22 gains its equity more evenly (example: any suited or off-suited hand from 34o to AKo has the same number of outs to hit a pair against 22). Thus QT drops in equity when the range is cut to best 50%, where as 22 does not.
So to construct 'ranges' you have to iterate by playing the range off against itself. If you are calling something an GTO opening range, then it makes sense that anyone who calls would only have a holding in this range.
You wouldn't be losing equity. Indeed you'd probably be winning it. The problem is that not everything in poker is about equity. The hand does not end the moment you see the flop. There are still three streets of betting. This means a lot of implied odds, specially when deep-stacked.
Also, it's not easy to define what the x% top-equity hands are, since you are not interested about equity againt a random hand, but against the opponent's range