I don't know that it ever held that much water.

I used to work for a company building desktop tools that were distributed to, depending on the tool, on the low end tens of thousands of users, and on the high end, hundreds of thousands. We had one tool that was nominally used by about a million people but, in actuality, the real number of active users each month was more like 300k.

I was at the company for 10 years and I can only remember one issue where we could not reproduce or figure it out on tools that I worked on. There may have been others for other tools/teams, but the number would have been tiny because these things always got talked about.

In my case the guy with the issue - who'd been super-frustrated by it for a year or more - came up to our stand when we were at a conference in the US, introduced himself, and showed me the problem he was having. He then lent me his laptop overnight[0], and I ended up installing Wireshark to see why he was experiencing massive latency on every keystroke, and what might be going on with his network shares. In the end we managed to apply a fix to our code that sidestepped the issue for users with his situation (to this day, he's been the only person - as far as I'm aware - to report this specific problem).

Our tools all ran on Windows, but obviously there were multiple extent versions of both the desktop and server OS that they were run on, different versions of the .NET runtime, at the time everyone had different AV, plus whatever other applications, services, and drivers they might have running. I won't say it was a picnic - we had a support/customer success team, after all - but the vast majority of problems weren't a function of software/OS configuration. These kinds of issues did come up, and they were a pain in the ass, but except in very rare cases - as I've described here - we were always able to find a fix or workaround.

Nowadays, with much better screensharing and remote control options, it would be way easier to deal with these sorts of problems than it was 15 - 20 years ago.

[0] Can't imagine too many organisations being happy with that in 2025.