I just can't understand why they would make this ancient OS so inaccessible. The OS is used by a limited and probably dwindling number of vendors of specialize

I just can't understand why they would make this ancient OS so inaccessible. The OS is used by a limited and probably dwindling number of vendors of specialized, complex and long-lived software originally developed for VAX/VMS. I was tangentially related to users of such software for a while; the vendor made the VAX->Alpha and Alpha->Itanium transitions, but saw the writing on the wall and ported the software away from VMS. VSI is not a large outfit, and they're a business. They don't need the hassle of dealing with hobbyists. It is genuinely great stuff, and with an active community it would probably re-emerge as a legitimate contender. It's a fascinating and superbly documented system, agreed. But a contender? Far too late for that, IMO, if it was ever in the cards (I don't think so.)