The limit to your size and shape is purely genetic.
Size, yes, but not shape.
One of the reasons physiques from the past appeared amorphous and lacking individual muscle separation and detail was because of a lack of training knowledge and opportunity (i.e. isolation machines, cables, etc.).
If you train with mostly compound movements, you will not get the look you could potentially get if you knew how to use shaping and peak exercises to bring individual muscles to their zenith.