Very few players consistently over or under perform their xg long term. Nketiah for instance usually scores around his xg. Last couple of months he hasn't, that's a statistical anomaly. Strikers like Kane and Haaland consistently over perform vs xg. That's not an anomaly, they're just lethal. Jesus scores under his xg season after season, it is what it is. If he didn't he'd still be at City as he has everything else going for him.
It doesn't really matter when he helps others score so often. It's all about balance. When Ode, Saka, Martenilli and potentially Trossard are all banging them in having a 20+ striker isn't a necessity.