Talking about character actually in my opinion it depends on the point of view because in the end no matter how good someone's character is it will not be considered good if we don't like it just like what happened to Ronaldo or other players who have a large level of popularity.
For example, in this case someone says that Ronaldo's on-field character is very bad because he is considered arrogant and wants to win alone but on the other hand not a few will praise him for his respectful and indiscriminate attitude in embracing people (players) who are smaller than him and not even a few people who praise his leadership on the field so I think it depends on the point of view we give because after all our assessment of a player will be tested because we like someone else like when someone will not like Ronaldo because of Messi or vice versa.
You're right. If we determine the character of a player, it will always depend on the personal point of view. If we are the fans of the player, we must highlight the good things about the player. So, the bad things about the player will be never showed on the description. But if we hate the players, we possibly don't describe the good things about the player. This will be too subjective, it is hard to have a fair comparison.
As for the performance of the comparison of Rashford and Ronaldo, I still feel that for the previous few seasons Rashford will have the potential and create his own era, it's just that for now with the performance that continues to decline every season it must be difficult to happen because believe it or not at Manchester United now especially for the last 2 seasons his performance has decreased and that is a fact that cannot be denied.
Yes, in the previous season, Rashford still played well and he could show his potential for the future. This season, the performance of Rashford is decreasing due to some reasons. One of the reason is Rashford having smaller time to play. It is quite different from the previous season when he almost played in each match. Another reason is Rashford no longer played as a striker, he played as a winger now. This also decreased the productivity in scoring goals. So, this is about how Ten Hag treats Rashford. Ten Hag doesn't try to optimize the potential of Rashford.