honestly I was wondering the same. the forum software is excellent. it loads faster, lightweight, uses node not something old as php, but it's so annoying to build the nodebb whenever you change some settings. plugins don't work, rebuilding/restart required to change the theme.
Those things aren't idea. But honestly, how often are you changing a theme? That's the kind of thing that we'd assume would be, like every few years perhaps? Live theme changes would be nice, I agree. But very low priority kind of stuff. I'd prefer just about anything get prioritized over that.