You brought up higher alcohol concentration. Natural ethanol beverages can be sweet because there is almost always more sugar that doesn’t become alcohol, because the alcohol concentration builds until it kills the yeast that does the converting.
Those actually interested can search-engine ‘ethanol-tolerant yeast’.
I think we should stop with daylight savings time.
Farmers complain that the extra hour of daylight
is burning up their crops.
Ahhh, but sugar remaining in wine - i.e. sugar that isn’t converted to alcohol, is considered a flaw in a “dry” table wine. It’s called residual sugar and it’s the result of a “stuck fermentation” which is what you’re referring to below.
Wine are purposely made with residual sugar (dessert wines) but in the instance I was referring to, that would be a flaw.