Well, I agree with this. His desire to leave Old Trafford, made the relationship between Manchester United and Ronaldo worse. and in the end ronaldo did not get the trust of erik, in the end he had to be willing to become a second tier player.
I don't think that is what is making Ronaldo fall out from first team preference of ten Haag. I would say it's more about performance rather than relation. Ten Haag knows how great player is but right now he has better option in that position who he thinks is giving more on the pitch than Ronaldo at the moment. I am sure once Ronaldo pushes himself and try more and give ten Haag a glimpse of what he can do then I think he definitely can make it back into first team selection for sure.
when cristiano managed to score 1 goal in the match against the sheriff (europa league), I saw the look on ten hag's face was very happy. Actually, Ten Hag really respects Cristiano and really wants Cristiano to be able to show his sharpness again on the field. I'm sure if cristiano continues to play well then ten hag will entrust him to continue as a starter and his contract next year will be extended by MU management.