I use a Fold 4. I am autistic.
I went into it assuming I would hate the crease. But decided the upsides outweighed that potential downside. But over a year in now and I don't even hate the crease. Honestly the thing I find the most annoying would also be on most other phones; Fold 4 has an underscreen camera with lower pixel density in front of it. Bothers the shit out of me. I've taken to having a floating button for screenshots/video and place that button directly over the camera circle. So instead of whatever is in my game looking stupid and annoying in that spot, I can just pretend the icon for the camera button has a weird design.
The upside for me is having access to a nearly 4:3 aspect ratio. I do alot of emulation of older games, so it's nice to have them be full screen again. Also the charging speed is pretty nice, can have the phone completely full from empty in just under an hour at max charging speed. Which means the 25% to 75% time is just nuts. Can plug it in and not get bored just from watching the percentage tick up. Lol.
I don't really have much use for it in folded bar form though, using it like an actual phone is of course better in that shape, but I didn't buy this phone because of how often I make or receive traditional phone calls. So it's mostly just a fast, useful tablet that I can fold up and put in my pocket. Honestly if there was a version without the outside screen, I would probably get that one. The only thing I use the outside screen for is to hang up at the end of a call. And I'm sure there is an alternate option for that. Could just have a tiny little info screen that had hang-up and speaker buttons. But yeah, if the outside screen isn't costing much to include, then whatever, I could take it or leave it.
I have the hand strap case directly from Samsung, I definitely recommend it. It's got adhesive strips that stick to the phone, designed to be put on once and never removed. It doesn't need to be cleaned under. Basically as minimal as possible while having the grip to the phone necessary to trust that strap with your $2000 phones life. Although I didn't quite pay that much, I always look for an open box deal. I got it 40% off.
But yeah, the crease isn't really annoying at all. At it's worst, when looking at the phone from an uncentered angle, it is visibly darker along each side of the crease, but looking at it straight on, which you generally would be doing, you can't even tell it's there. You have to touch it to notice it, but it's smooth enough that it doesn't affect playing games or anything.
I was worried it was gonna be much worse when thinking about it before I got hands on. So when my sister got a used fold 3, I borrowed it for a couple hours to play some specific games I wanted to try out. And I wasn't worried anymore about spending so much for a fold 4.
The weight was an issue originally, took about 2 weeks to get used to it, and then about a month later I got the strap case and it would have solved it anyway. It's lighter than a hand-held gaming console, and I'm sure a few of us used to hold those for hours when we weren't as strong as we are now. The original issue was mostly when trying to hold it one-handed from one side of it. Or gripping accross the phone in folded out mode. I have decently big hands, smaller hands would have made it more than a 2 week issue. But yeah, if my hands were smaller, the problem would have remained until I got the strap case, then you hold the phone from it's center of weight and your hand is in a comfortable position while doing so. Or I just tuck one finger tip into the strap and two more on the outside of the strap and hold the phone from one side still. Comfortable and distributing the phones weight more evenly.