Football doesn't work like that, adding and subtracting goals scored by individual players. Individual stats help us learn about players but success is still contextual.
Obviously, there's no way Davies would score as much as Sigurdsson. But here are some things he can help with:
- Preventing the opposition from cutting through us at will. Davies is useful defensively and with a better defense, we don't need to score as much to win.
- Providing our defenders and midfielders with another option in possession so that opponents can't take Gomes out of the game and put all of the heavy lifting on Gana, the CBs, and the fullbacks (like they have been since December). Davies is one of the best in the squad at moving without the ball and making himself available to his teammates.
- Forcing the team to play a little deeper, giving the front three more space to work. Imagine how much more effective the likes of Richarlison, Bernard, Lookman, and Walcott would be if they weren't facing packed defenses all the time. Here's where you recover those "lost" goals.
Nobody can say for sure if all of those things would happen but it would be a worthwhile experiment, at least.
Silva's spent the last month tinkering around the midfield -- mixing up the attack, mixing up the defense, adding a defender, subtracting that defender, mixing up the attack again. It's time for him to try something to get a grip in the middle of the park.