What is the reason Light Sport Aircraft (LSA) minimum speed is limited? I saw an explanation about Icon A5 Light Sport Airplane (LSA), it is said that according to FAA regulation, its stall speed NOT LESS than 45 miles per hour (mph) or around 39.1 knots or around 72 km per hour (kmph). Which is mean, its minimum speed is that 45 mph. I was curious that minimum speed is limited.
Than my question is, what is the reason FAA limits the minimum speed of an airplane? Is that stall speed limitation also applied to another type of airplane?

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Edit: Some conversion from mph to knot was not clear. Should be 45mph or 39.1 knots.
Edit 2: I added the minimum speed not less than 45mph.
The FAA mandates a maximum to the stall speed, not a minimum. The minimum speed must not be higher than a given value.
The minimum speed is limited in order to reduce the risk and severity of accidents, especially during landing. The same was used in FAR 23 where a speed limit of 61 knots was mandated for singe-engined aircraft and multi-engined aircraft of 6000 lbs MTOW or less (§23.49 (6)c).
A slower stall speed translates into a slower approach speed and shorter landing distance. Both help to prevent accidents by giving the pilot more time to get the landing right and come to a stop without crashing. Also, the energy involved is smaller so if something goes wrong the accident is more survivable.