Having physical strength does play a role in bowling. Some people have more than others but the bowlers with the more physical strength, for the most part knocks down more pins. I have seen big guy throw light bowling ball super hard and since the bowling ball is so light, the bowling ball would just bounce off the pins.
They needed to use a heavier ball for more pin action. Sometimes I see older bowlers bowl and since they are not using much physical strength, their bowling ball tends to bounce off the pins as well. So physical strength does play a role in bowling and knocking down pins back and the weight of the bowling ball plays a role as well. This is why small kids bowl and they don’t knock down many pins due to the lack of physical strength but you can still bowl but just know that some bowlers do need some physical strength.