Short answer: no, they don’t.
Modern compound bows use that cam to lessen the power needed to hold.
Older bows are like holding a spring extended, the further back, the greater the force needed.
By modern I take it you mean compound bows. No other types of bow have that. The force you need to pull back is at its maximum when at full draw. The exact scale of 0-100% through the draw varies with different bow designs, material and even age as it can permanently deform with repeated use.
I know that modern bows with the radial cam thing have different hold vs draw requirements.
Not being a bow-knower, do the other sorts (long, recurve, etc.) Not have a similar thing that can happen?
Short answer: no, they don’t.
Modern compound bows use that cam to lessen the power needed to hold.
Older bows are like holding a spring extended, the further back, the greater the force needed.
By modern I take it you mean compound bows. No other types of bow have that. The force you need to pull back is at its maximum when at full draw. The exact scale of 0-100% through the draw varies with different bow designs, material and even age as it can permanently deform with repeated use.