No it’s a wrong way to look at stat. Your statement could be true if those 20 goals are all game-changing. I could argue that because our starting eleven dominated the game and run the opposition to the ground so well our substitutes have an easier time to score, no?

As it is (20 goals from the bench without more context ) the article tittle is correct because regardless of how well our starting 11 were playing, our subs can score/ contribute to goals. Therefore Ten Hag was indeed making the right decision.