Controlling your taps/alternating is an skill regardless of the speed, the hardest range for most players who only play fast things should be around 140~165, because lower than that if you're fast enough you can just single tap, and higher than that the songs aren't exactly slow anymore and are usually less complex to follow.
And for reading, each AR requires adjustments for reading it properly, knowing how to it is an skill.
This map is a good example of how going slow can be hard: https://osu.ppy.sh/s/290040
And for reading, each AR requires adjustments for reading it properly, knowing how to it is an skill.
This map is a good example of how going slow can be hard: https://osu.ppy.sh/s/290040