Wrecking yards in general are dying, especially self serve ones. Even UPI Elizabeth is looking pretty sad these days, stock hangs around forever and doesn't circulate.
IMO Marketplace and backyarders are killing them off. Half the time it's cheaper and quicker to find someone local wrecking the car you need than it is to go to these yards. On top of that the EPA's on their ass constantly about polluting the ground and the public liability insurance is off the scale for people coming in and pulling parts themselves.
That being said I'll miss UPI when they are gone. I haven't been much lately as their stock of 2nd gen commodores are drying up. They are mainly getting VT-VE now.
The margins for running a self serve yard would be razor razor thin, I'd hate to see how little their staff get paid.
My first job was working at a wrecking yard. It’s sad to see them go and all the ones that were UPI around my way closed up years ago.
Your reasons for them disappearing are on the money but one thing I would add is that most people generally don’t work on their own cars anymore, which is where most of their business came from.
The proliferation of cheap eBay aftermarket parts would also have made an impact. In my day when I was growing up you basically had new (expensive) genuine parts or secondhand (cheap) genuine parts at the wreckers. There weren’t really any other options for a lot of part so unless you were made of money then off to the wreckers you went.
I’ve been part of the problem as well as I haven’t been to a wrecking yard for many years now (well over a decade) as I generally have enough money to buy new parts now instead of secondhand ones.