BGG could use an "Out-Of-Print" flag.
That way people would know from the game's frontpage whether it is easily available or not.
Or like a 'click here if you want it, but can't find it for any less than 2x MSRP'. Once you see it pass a threshold, you know it's OOP.
Now, figuring it out when it finally gets reprinted...
Definite issues with OOPedness -
IP issues. The company goes out of business that owned the rights...kiss that game GOOD-BYE. Same with contested rights.
Special figures. The pieces were printed years ago, and they would need to remake the molding to make it work. It's not gonna happen.