Am not sure if any of those will make a difference. But that’s my understanding also - more sugar makes the finished product taste less dry.

Saying that, as someone who is always halving the sugar content of American recipes, it doesn’t usually seem to be much of an issue if you eat whatever it is whilst it is still warm from baking. Also, if you heat it up again later, you get that ‘just baked taste” back again - so my advice when reducing sugar is to eat your project immediately, and if you can’t, then let it cool and put it straight into the freezer. Then heat it up just before you want to eat it.

Another route to reducing sugar in recipes is to stay away from US recipes. Japanese recipes tend to have more of a tendency towards less sweet products (not always though!).
There is a great technique for injecting moisture into baked goods without relying on sugar. It’s called the “water roux” method, sometimes called Tangzhong or tang zhong, sometimes called yudane. It often requires an extra step in the baking process - which you might need to start the night before - but it means that your dough won’t be relying on sugar to lock in moisture.
You’ll find plenty on the net or in YouTube using “water roux” or the other search terms.