Erling Haaland is unarguably the most prolific striker in Europe at the moment and that numbers strongly backs up that claim. The number of goalscoring records he's broken and created after his first season at Manchester City last season is a true testament that he's gonna be one of the biggest players of his generation.
However I think he's a good finisher that's always at the right place whenever his team is on the attack. His foot works on the ball whenever he's in possession of the ball isn't as good as his finishing and that's the area he has to work. He mustn't rely on good passes to score goals. What makes a striker to be termed "complete" is if he can fall deep when his team isn't breaking the defense, collect pass, dribble past one or two players before scoring or creating a good chance for his team to score. If Haaland can learn and efficiently know how to dribble with the ball, he'll have better goalscoring records than Ronaldo and Messi in the future if you ask me
I guess that there is something that could be considered probable with Mbappe as well, that dude is a prolific striker but not a lot of people consider him pure striker since he was evolved from a left winger as well.
I would say that it's going to be something that would matter, because if we are talking about a pure striker then Haaland could be the best one. He had a great year at City last year obviously and he is a great scorer without a doubt but at the same time if you took Haaland out of City and put him at PSG and instead you took Mbappe out of PSG and put him at City then I bet that Mbappe has at least as much goals as Haaland did, he would be a good fit for that team because he would be running around passing.
If it comes to physicality and finishing, I will say that Erling Haaland is the current best in my opinion. But if it comes to pace and overall great attributes, I will say that Mbappé is the one. I personally think that if it was not for PSG absolutely ruining Mbappé, he could actually have been a better player with more achievements to Show.
But on the other hand Haaland has been with a team That is a great one. His team is almost the perfect team that any player could ever ask for. So he already had a Headstart. It will actually be interesting to see both of them playing for a team that is actually equal in terms of strength. Probably then we will be able to judge their actual quality.