Ounces per plant is not a useful statistic.
Ounces (or more commonly grams) per watt of light or oz per sq ft of grow area are useful.
One plant could fill a 4 ft x 4 ft tent and yield 2 lb, but it would take a long time to spread the plant out to do it.
Or 4 plants could fill a 4 x 4 more quickly, and yield about the same, unless big central colas become an issue.
Assuming adequate light, grow style probably has the biggest effect on yield.
It's easy to get an oz per sq ft in hydro, or in hydro-like setups such as hempy buckets and autopots.
For a single normal plant, 2 oz should be easy in most setups.
The high humidity that the VPD chart recommends would probably get you that with your present grow style.