I do think that the majority of every football fan do believe that Haaland will get this but we should also remember that not every year the one that deserves it the most ended up getting it. Lets realize that Messi won the world cup and the world of football may want to give him the reward one last time.
Not that I would be bold enough to say that he deserved it more than Haaland, that dude was the core piece and the highest scorer of a team that won the premier league, fa cup and UCL all on the same season which could be one of the hardest things ever and not many teams has done it for a long time. But at the same time not everyone who deserves it gets it like I said, which means that we are going to see Messi having a possibility of winning this one as well and should be thought about when betting if you are betting on this.
I think you mentioned an important issue here and that is the lobby of Messi in the world is still bigger. But he also really won something and it has always been a pleasure to watch him play. I agree that Haaland rocked all competitions and it's a pity that Norway most likely won't make it very far in a World Cup in the foreseeable future. This puts him at a disadvantage every few years when this award is given. But I think I would be ok with any of these two guys to get the reward. I don't think it would feel like betrayal or anything as both have done incredible things in that season and Haaland deserves it a bit more, but Messi wouldn't be a bad winner.