You can blame IBM for that. The fact that they haven't made it easy for security researchers (or anyone really) to tinker hurts the platform.
Up until a few years ago, there was no legal way to run z/OS on hardware that wasn't a million dollar hunk of iron from IBM. IBM has since made a product called Rational Developer and Test Suite [0] available. With it, you get an emulator and a licensed copy of z/OS that you can run on x86. Except it's $9,500 / year.
The only saving grace is an open source project called Hercules [1] which emulates the z/Architecture. If you don't mind breaking some copyright laws, there is no technical reason why you can't download a copy of z/OS and run it under Hercules. But good luck finding the latest version. Want to test your research against the latest maintenance levels? Good luck.
Up until a few years ago, there was no legal way to run z/OS on hardware that wasn't a million dollar hunk of iron from IBM. IBM has since made a product called Rational Developer and Test Suite [0] available. With it, you get an emulator and a licensed copy of z/OS that you can run on x86. Except it's $9,500 / year.
The only saving grace is an open source project called Hercules [1] which emulates the z/Architecture. If you don't mind breaking some copyright laws, there is no technical reason why you can't download a copy of z/OS and run it under Hercules. But good luck finding the latest version. Want to test your research against the latest maintenance levels? Good luck.
[0]: http://www-03.ibm.com/software/products/en/ratideveandtesten...
[1]: http://www.hercules-390.eu/
[2]: http://mainframed767.tumblr.com/post/40836059586/instruction...