I don't think it is possible to back up that statement. In 1999, machine interoperability was not as critical as it is today.

Last time I worked with OpenVMS was 2014 going into 2015. The system in question was an orders management system for an online pharmacy. It. Was. Hell. The Alpha-based cluster was being rebooted daily because it would run out of memory constantly. They would purchase spare parts for their cluster from a local company that specialized in NOS and recovered boards bought on eBay. We had some laughs about that!

The code was ancient--some of the earliest comments in the sources dated to the 1970s. There was no source control, no modern compiler, no debugger, no anything. We used sockets to communicate to a sort-of SOAP service to get data out for reporting but it was incredibly, tearfully s-l-o-w.

The UI was terrible. The users of it complained endlessly, and rightly so. We're talking about a time when most everything out there was built on a HTML Web-based system for at least a decade already and people were well used to Web interfaces. And here these poor souls were still using terminal emulators to connect to a green screen application and had to to have all kinds of odd work-arounds and policies to get by with all the bugs and strange anomalies. Did I mention the horrible uptime?

The management kept wanting more, more, more out of the enterpise Java team but all the technical limitation were on the VMS side. Meanwhile, the syadmin who ran it was a complete turd of a human being, only trying to keep his job there lest he be forced into retraining into some actually useful technology. Worse, he actively campaigned against any technical changes we wished to make (for fear of losing his fiefdom) and so undermined my team to the point where management became openly distrustful of us. "Can't trust that new-fangled Java stuff!" "You mean the actually reliable, high-performance stuff? That stuff?"

The company unbelievably doubled down on this odious mess by purchasing the source code for the system from the vendor that owned because that vendor wanted to wash their hands of it and get out from under the hell of supporting it. When I heard what my company paid for that code I nearly had a breakdown because it was eye-watering. I could have re-written the thing 5X over and extracted the data for that kind of coin. If that's the kind of idiocy it takes to manage a large corporation in America these days then I should be a CEO because I am far more than qualified! I could show up one day a week and do less damage. Had I had a free hand at that company I could have done incredible things, but it was not to be.

Worse still, now that they owned the sources, they thought they could do something useful with it and hired a contractor who had once sort of worked on this same trash at another firm. He was charging $250/hr to be there and was the most obnoxious developer I have ever worked around. He set the bar very low on personal hygiene, decorum, and general bad behavior around the office. They had to move him out of the cubes and give him his own room because of so many complaints about odors and um, noises.

Looking back, it seems like everything related to VMS was these kind of obnoxious people--I used to hang out with the sysadmins who managed the clusters at the college I attended and they, too, had that VMS/DEC obnoxiousness disease. I don't get it, I'll never get it, am happy to be far away from it. DEC had its day, they failed to adapt and modernize and went away. You don't see this same nostalgia for Wang Computers and Wang was the true original in the mini space.