It isn't just about ability though. Age, profile PR etc all come into it.
Kane is nowhere near the peak of his powers, that was 3/4 years ago. There is a reason be plays like he does now, cause his body can't handle playing like he did before. I'm not disputing how good he is, my point it as a buyer there are other options that are just as attractive. Nobody has bid for Kane before, what suddenly makes things different now?
If you can potentially buy Haaland and Kane for the same money, what's the benefit in buy Kane? That he's done it for longer? In that case pick up Aguero on a free, buy Haaland and your sorted. Likewise how long has Mbappe got left on his contract, a year. So you could fudge about with Levy all summer, or take that supposed 90 million, give it to Mbappe as a signing on fee and then get him on a free.
There's more to any potential transfer then simply saying a big club is gonna come, make and bid and that's then end of it. Utd couldn't even get Sancho over the line from a notorious selling club like Dortmund.