Wait, what? What do you mean?
you hold an xbox controller like making a finger gun, with the important functions like shooting etc on the triggers, so that's where your index finger is resting most of the time. this moves the thumbs forward, which makes the location of the stick on the left side more comfortable (doesn't explain the right side, that's why asymmetric never made much sense). the way you're holding a xbox pad is also a reason why people really like back-pedals on them.
a dualshock (traditionally) is more like grabbing a nice pair of tiddies from behind, with the important functions on the bumpers, not triggers, and the pad resting on your palms. this way the thumbs are lower and further apart, so you can move your thumbs more freely depending on the size of your hand/length of your fingers - index on bumper, middle finger on trigger, hence "claw" (both sticks is how most sony movie games are controlled anyway). you could even go one step further and shift everything so the index fingers are resting on the d-pad/buttons.
however, sony in their infinite wisdom adopted the xbox input scheme with the ps4, putting the important functions on triggers. this means you're now supposed to hold a dualshock like an xbox pad, even if the ergonomics are different, and that's why holding the controller/using the sticks this way feels shit and like there's not enough space. on ps4 they were at least smart enough to include an "accessibility" option to swap it back to the classic layout, dunno if the ps5 supports it. of course doesn't change the screen prompts (unless a developer includes the option himself, but given how much consoles are known for their customization, you can prolly guess how many do).
plus haptic feedback might be nice and all, but I doubt it will beat shoulder buttons for simple input speed and accessibility - with the xbox input scheme you have to move your index finger up if you want to use the shoulders (never seen anyone use the xbox triggers with his middle finger, since it feels off and is less comfortable, and given the asymmetry it makes trying to claw an xbox pad look even more spastic), while you always have a finger on both when clawing a dualshock. and it allows you to still use your d-pad with your index finger if you need it, while on xbox again you have to move your thumb and can only ever use one at the same time.
it makes a bit more sense when you look at the original versions and where they come from. the dualshock(2) doesn't have triggers, while the xbox duke controller is designed like a toy (I assume a faggy microsoft designer thought "hurr triggers, just like a gun!", but at least it makes sense design-wise since most people instinctively will pull the trigger with their index finger EDIT: thinking about it they probably stole the idea from the dreamcast). with the dualshock 3 sony adopted the triggers, but treated them mostly like extra buttons just like before (another indicator is that shoulder buttons are still L1/R1, it doesn't make much sense to not start with your main inputs). ds4 is when they started to get faggy like ms.
TLDR: they were designed with different ergonomics in mind, till sony fucked up.