You shouldn't judge Bellingham only in one final match against Dortmund, but look at Bellingham contribution so far when he played in the UCL or La Liga, after all, the two goals he scored, one of which was also an assist from Bellingham, is clear that this is good contribution he made.
In the UCL Bellingham provided 4 goals with 5 assists and for La Liga he provided 19 goals with 6 assists for Real Madrid, isn't this satisfying result, Bellingham has great potential in the future.
But on the other hand, Mbappe will be able to provide much better performance in the future, Mbappe and Bellingham plus Vinicius and Rodrygo can become very strong front line collaboration in destroying the opponent defense.
I want to see if next season Mbappe can get the UCL title in his first season with Real Madrid, this would be very impressive if it could really happen and Mbappe will definitely be very happy and satisfied when he gets it.
But it won't be easy because several other teams will definitely be tough opponents for them, but looking at the conditions next season, the opportunity to defend the UCL title is possible.
Bellingham is a player who's got versatility in his palms, he's majored as a midfielder and does exceedingly well both at maintaining the mid pitch and heading upfront but that doesn't guarantee the fact that it's best to switch his usual position and experiment on giving him a new role. Since even as a midfielder, he finds comfort and ability to be versatile and it works well for him then it's best for a coach to maintain him on that grounds and keep basking in the good he's doing at that position.
For a player's major position to be switched, it'll only cause a decline in performance because the whole role would seem new and the player who's got no idea on the role he'd be playing, will just be lost and will slack which may in turn get the team affected. Every man is important in a team and so is every role dey play so each one should be left to do his duties and ensure that its done well instead of taking every game for an experiment. It'll only diminish the squad gradually. Madrid boys have always had a good game for the team even though more than much is been expected from them but for a game in a every competition, they always did really good.
This only resonates the sermons of how well built up Real Madrid squad is. The young players are definitely an extra advantage to the team's strength. Real Madrid have won several titles and Mbappe joining the team would increase their chance of winning the UCL and much more titles. The Spanish side is filled with young, vibrant players eager to go for and secure trophies with a good managerial support too. This is actually an atmosphere that'll be conducive enough to receive and accommodate the French star. Mbappe knows that with Madrid, he's set out to do even better than he's already done. There's still a more to come from him. He just needs to be in the right team and squad at the right time.