That's really a topic should be debated.
Does direct pass = counter attack? Does short pass = keeping possession?
In my opinion, if I am right, passing slider doesn't mean to be strictly allow a player's passing style, but just the % for him how to play the ball.
Shifting the slider to rightward, that means you give your player a chance to play direct or even long pass up to the field. But of
coz, they will not pass all the ball directly! They will play short and try to play directly when they think it is a chance. On the other hand, shifting to leftward means you are hindering your player to play long balls.
When you attack, my opinion is that allowing you player to play every type of ball, not only short pass. That means I will try to slide rightward for the slider and set to direct pass when I want to attack, or even long pass when I really need a win.
On a contra, shifting left when defending can keep you possession so that your player can try to build up the attack.
But this could be contradictory for counter attack. Counter Attack requires a long or direct passing so the ball can be pass up to the field ASAP. That's a problem that I cannot find a solution yet.
Meanwhile, if your team has a style to play, for example, have tall or fast player all the field of
coz you play it direct. Or with player passing 18+, you should use TTB + short pass, you should use your style to play. What I am saying is that normal team doesn't have a specific style to play.
To conclude, attacking = direct is no doubt for my sense. But for denfense, just depends on your situation, holding for a draw or try counter with direct balls but it will be risky for losing possession or even licking goals.