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).
The Cristiano interview, felt like there was a lot of unnecessary outrage over Lukaku’s interview, players give interviews to similar effect all the time. Cristiano simply wanted a way out and chose to throw everyone under the bus to feed his ego. There was a way forward with Lukaku’s interview, Chelsea simply reacted in the worst way possible.