Top speed can be a deceptive measure of how effective a player's speed is in reality.
For example, Phil Jagielka, a few seasons's ago, was clocked as the fastest player in the Premier League at 36km/h, van Dijk registered the fastest top speed in last season's Champions League, and Kai Havertz has a similar top speed clocked in the Bundesliga to Hakimi.
What really counts is how many strides does it take to reach anything approaching that speed. Mbappé looks quicker than everyone else, not only because his top speed is 36km/h+, but because it's combined with acceleration that also ranks in the top bracket. Davies, for Bayern, is another rare player that combines the two; and he will beat Hakimi well if they get in a race tonight (and I hope they do because it will still be fun to watch!).
I agree Hakimi's first touch is good; I would say he's a capable dribbler but relies more on his speed and is much better when he's carrying the ball and going at opponents rather than trying to beat people in tight areas from a standing start the way Sancho, for example, does for fun.
All of that aside, I do agree Hakimi is an extremely good player and I would love him at Arsenal.