Both caused a disruption in each teams season, adding unnecessary drama and conflict. Both players also had high expectations of them, but both ended their time at the club poorly due to their interviews (yeah Lukaku’s still technically at Chelsea, but he doesn’t really feel like one anymore with him getting loaned out every season).
I would love to sit here and tell you that Lukaku’s was worse - it was. But Ronaldo dropping that interview right before a World Cup definitely takes a medal of its own.