I think you're missing the point completely here. Mbappe plays a completely different position to Kane and could actually play in the same team as him for City. I'd argue that Kane and Mbappe in the same side would be exceptionally potent when you consider Kane's ability to drop deep and create for his wide forwards (see his link up with Son last season). The key point being that Mbappe cannot offer what Kane does to a team as a 9, which is a more total football style where he plays as a hybrid 9 & 10. Haaland, whilst playing the same position as Kane, plays it very differently, with him being solely the focal point of the attack. Guardiola does not favour this type of 9 in his system.
If you look deeper into their stats then you will see that Kane is on a different level as a passer of the ball to both those players which strongly suggests the reason as to why Guardiola would want to sign him over those two players, although to reiterate that only Haaland is a meangingful comparison anyway.
When you consider the levels of the leagues the respective players compete in, look at Kane's npXG, then I'd argue that it would be reasonable to expect a similar level of goal output as those two players in a top league like the PL when he plays in a high chance creation side like City. That's whilst adding the qualities to the team that the other two players can't in the 9 position.
Go into the full report for the passing stats.
https://fbref.com/en/players/21a66f6a/scout/365_euro/Harry-Kane-Scouting-Report
https://fbref.com/en/players/42fd9c7f/scout/365_euro/Kylian-Mbappe-Scouting-Report
https://fbref.com/en/players/1f44ac21/Erling-Haaland
Oh lord!
Kane last season (where your stats are from) and Haaland is completely different striker types. Kane dropped deep alot more (15,5% of his touches in the boxes), got involved a lot more and used more touches per pass (1,56 touches per pass), while Haaland spent as much time as possible in the boxes (28% of his touches in the boxes) and played direct whenever possible. Mbappe often plays wider and gets involved a lot more than both the other two. Even then Harry has a pass completion rate lower than both the players we are comparing him to here (Harry 70%, Erling 74%, Mbappe 78%). His xA was alltime high for him last season with 0,23 per 90, just a tad higher than Haalands 0,21 per 90, even though Harry attempts 50% more passes. Kylian is at 0,26 with 95% more passing attempts than Haaland. Haaland by far the most direct player of them and never takes freekicks or setpieces.
When it comes to finishing and getting in to good scoring positions, Haaland is in a league of his own.
Do you really think Harry would increase his npxG with 38% if he played for City?
Harry shoots a lot and wastes chances like few other top strikers. He shoots from all angles and all distances, while Erling chooses his chances more carefully while also being a lot more clinical.
Finishing and goalscoring:
Harry:
Shots on target: 36,2% (25 percentile)
Goals per shot: 0,14 (40 percentile)
nxpG: 0,55 per 90 (90 percentile)
npG-nxpG: +0,03 (57 percentile) He outperforms the expected output of his chances by 2,7% (a bit over average for strikers)
Erling:
Shots on target: 54,3% (96 percentile)
Goals per shot: 0,29 (99 percentile)
nxpG: 0,76 per 90 (98 percentile)
npG-nxpG: +0,22 (95 percentile) He outperforms the expected output of his chances by 29% (outrageous for a striker)
If you have creators in your team and want a guy to convert your chances, Kane is not your man if you can choose between those two. Haaland and Mbappe also adds something a new dimension to your counterattack.
If you want a guy that drops deeper and involves himself more in the buildup, then sure Kane could be a better option. Will he score more than he does for Spurs? Hard to tell as he is shooting more often than anyone in the PL already (and Haaland and Mbappe). Kane shoots on average 4,03 times per 90, while Jesus and Aguero both sits well below 3 shots per 90. So it will be interesting to see if the City signs him.