You've gut the nail on the head: dig was designed with the needs of the 90s in mind, where terseness was a virtue (if your ram can be usefully conveyed in kilobytes, you need terse tools).
Due to backwards compatibility, the output won't be changed. Due to backwards compatibility, stuff is the tool that's installed by default.
Both can't be changed (it would break too many assumptions many scripts and programs have).
However, there are multiple dig alternatives. You just have to install them.
I liked jvns' suggestion to add a +human option - plenty of tools have a -h output option which is nicer for quick interactive use, and I value their existence (e.g. I use both 'du -h' and 'du -k' semi regularly depending on if I want to read the results or throw it through an analysis script).
dig already translates things like record types from integers to strings, why not use the full, descriptive names for these flags as well? Why shouldn't I be able to dig +pretty domain.example?
I suppose dig is mostly maintenance mode these days, but it's quite annoying to see so many tools rely on it when it's so... 90s.