Why no comp.sys.ibm.r6000?

[raymond thomas pierrehumbert]

I notice that this group (now that I've finally found it!) basically
serves the function of "comp.sys.r6000".  So why is it stuck under
unix?  We have comp.sys.hp, not comp.unix.HPUX, and comp.sys.apollo,
not comp.unix.DOMAIN.  What's the history here?  
    Is anybody interested in establishing comp.sys.ibm.r6000 and
moving there?