If Ronaldo ends up moving away from Manchester United during the summer transfer window, then it will only make Ten Hag's job even more complicated. I think you're right, Ronaldo was included in Ten Hag's plans this season
Do you think everything will fall apart with Ronaldo moving to another club? This is a football club and to win a game, it needs 11 players to play well and not just a single Ronaldo therefore even if he decided to leave the team then I dont see how Ten Hag's plan will fall apart. If Ten Hag cant put up another plan which doesnt include Ronaldo in it then I honestly dont see how he will fit in the club