If the display has been a 'bust' 3-4 years from now Apple will probably just stop selling it. Period. As for dramatically lowering the price. ...
https://www.apple.com/shop/buy-mac/mac-pro
Apple is STILL selling the old as dirt Mac Pro 2013 at the same price point.
What may happen is some folks buy them and them dump them in 3-4 years as chase the then newest tech porn 'shiny' that they can't live without. There is always a few of those folks out there.
In about 4 years I'd expect Apple to churn out another "un-obtainium" monitor with equal "Buck Rogers" tech specs because XDR just isn't enough. More colors , more pixels and more , more, more. More likely, the curent one will be discontinued/superseded rather than discounted.
The latter probably depends upon where Apple is going with the iMac displays. The 5k model is coupled to the iMac as most other monitor vendors have dropped that size. Likewise it seems to look like only Apple has asked for this 6K display ( I haven't seen it pop up in the "what panels are folks working on lists at places like tftcentral.co.uk ) . So if it is never attached to a much higher volume product ( e.g., iMac Pro or something else) then it is unlikely LG would want to ship one.
I would agree there isn't a chance at all these drop in price. Only option is used and even then it will hold a lot of value.