I’ve seen rare places where the server has a handheld and every single item is always individually charged. Then they can keep things separate or combine it however you want.
But, I’ve seen that maybe twice in my entire life. Once might have been in Vegas. Everywhere else is as you say; it’s just not a reasonable post-meal request.
Yeah there's a Pho place in Seattle I'd go to lunch at (iykyk) where we'd regularly have 20 people at a table and pay individually. But they didn't even use the check for that, they'd just ask what you had and ring that in as they went around the table with the handheld. Literally the only place I've ever seen that even offered to split a check at a table with more than 3-4 people.