Bruno Fernandes has scored in 6 out of 26 games this season in the Premier League - that means he has failed to score in 20 out of 26 games. He has assisted in 5 games, he has thus failed to register an assist in 21 out of 26 games. He has assisted and scored at the same time in only one game, which was last week against Leeds. For a very attacking and very involved player dictating most things by default, these are not brilliant numbers at all.
You are not able to see both sides here it seems. Certainly not our biggest problem, but also difficult to know if he is the reason for our other attackers not shining as much as they can. Is he taking up too much space/their space and/or not involving them as much as he could? If so, it is not for certain that better attackers would love to play with him, that chemistry isn't created because he refuses to give up the ball when he should at times, which is very often. His work rate is very good, seemingly, but how successful is his constant chasing, does he leave his own position too often and could it create defensive trouble because he takes on the tasks of other players, who then fall into no man's land? He is in my eyes very unstructured in his work, he needs to be controlled better. Brilliant footballer? In some games yes, in many others not so much. To summarize, he is not consistent, his form goes up and down, we cannot rely on him like City can on de Bruyne, or Liverpool with Salah or Mane, he is far from having their stability. If a player is brilliant or missing in every other game and which has been the case with him this season, he is not a brilliant player period. Consistency and ability to perform against different types of teams = key, his output against better teams is very bad. Both in terms of goals/assists and the eye test.
Good luck to the one having to work with him to become a better player for the team, to raise his lower level, so contain his positioning and so forth. In the end, it might just be very clear that he is our "best" player, but also perhaps out biggest problem when trying to go from good to great as a team.