Linux assures that IBM can happily sell lots of IFL or general purpose CPUs which are necessary to compensate for this inefficient use of
mainframe resources.
Oh, and Java! They are very happy that their customers convert their mainframe stuff to be mostly Java, because it's so inefficient and causing them to buy more processing power from IBM!
two specialty mainframe processors designed for Linux
Seriosly? That's just marketing FUD. They are not designed for Linux, they just have some features deactivated so that z/OS can't run on them, so that they "could sell them cheaper".
Take an astronaut to launch.