Some of it I think is (well for me anyway) I will dial in a module to the sound I hear in my head regardless if the module is known for that sound100% especially when we are talking hi gain stuff , the higher the gain the less dynamic range and more compression
if you take same player
Same guitar , same pickups
Same cab , the end result if you had an amp switcher going between 3 or 4 real heads would be more like subtle differences in many cases ,
The difference in feel to the player would likely be more noticeable
Most of the modules I have are a similar flavour but there but I can detect the subtle differences.