Thanks - this is what I thought - there are no real alternatives to Apple Studio Display.Not with those criteria. I'll be surprised if anyone can point out a product like that (even absent good, or any, built-in sound and webcam) at that price. 5K Monitors seem to be slim pickings; it's currently a 4K (and under) world for the most part.
If I went looking (and even then, I'm skeptical it could be done now), I'd anticipate one of these scenarios:
1.) Black Friday/Cyber Monday/Amazon Prime Day sales - Apple doesn't do huge mark downs but competitors do. Even then, 1/3rd price or cheaper is a tall order.
2.) Refurb or used. Not an option with reliable availability, but if you happened to know someone with an LG 5K selling it to buy an ASD, etc...
3.) Take a chance on a 'no name.' The stereotype would be a Chinese (no knock on them, they manufacture a lot of high end stuff, too) imitation product alleged to be close enough but much cheaper. I wouldn't expect the build quality.
A known brand name product meeting your criteria new ought to get a lot of discussion on Mac Rumors forum, YouTube, etc...
Sound and camera are NOT a must by the way. However, 5K, 27", IPS high-quality matrix are a must.
Yes absolutely, Used and Refurbished are an option. Today I was in the Apple Store again with a friend, just cannot believe how stupid is that iMac is much thinner, has a powerful desktop Mac computer inside it and it's still cheaper than ASD, which is just a monitor.