I remember back when I did run two forums, I fixed issues myself. It's PHP, HTML, CSS, and JavaScript. None of that is magic.
If you're not fluent in these technologies, it's all magic. Getting cross browser/device/format/layouts to work is a dark art. Still. Even today. You seem to think that the legacy, 20+ year old VB code base, with incremental improvements made over time, across no doubt several versions of PHP, is accessible. I don't know that it is or not, but I'm skeptical.
Another board I am on, using VB3, did "fix issues themselves" over time. They were not able to successfully migrate to VB5. It didn't help that the person who did the fixes and changes over the years had died, nor did it help that the current admin was more a QuickBasic64 guy than a PHP/CSS/HTML/JS guy. They actually hired someone to do the conversion, whom one would casually assumed was more a PHP/CSS/HTML/JS guy, and they still failed to do the conversion.
They switched to XenForo and the conversion went really well, the problems that they are having are being managed by help desk tickets to the XenForo folks.
If you refuse to mess with that, changing to any other software won't help.
Pretty sure the folks here do NOT want to mess with that. They want to soak boards in alcohol and recap them. They want a system that meets their needs, and works with checkboxes and buttons, not ssh, vi, and PHP/CSS/HTML/JS hacking that won't be supported by the vendor.