Most SWG systems are undersized and for outdoor pools need a higher CYA to be able to limit chlorine losses from sunlight so that the SWG is able to keep up. Also, minimizing the needed SWG on-time reduces the rate of pH rise that is also a problem in most SWG pools. This is why the SWG chart shows a limited and higher CYA range.
Spas are very different if they have covers. They aren't as susceptible to algae since their covers keep out most light and when the spas are run hot (towards 104ºF) algae is inhibited. In a spa, bather load is much, much higher than in a pool so most chlorine is added right after a soak to handle bather waste so the FC level generally gets quite high soon after a soak. Since most people want to soak with a low level of chlorine in a spa to minimize noticing its effects, the usual rule is to add enough chlorine after a soak so that one has 1-2 ppm FC at the start of their next soak. If one does not soak every day or two, then in between soaks one would usually target 2-4 ppm FC with 30-40 ppm CYA so the minimum most of the time would be roughly similar to the SWG minimum of an FC that is 5% of the CYA level, but this applies for manual dosing as well (again, because the spa is mostly covered, the water generally hotter, and the chlorine level often varying higher).
Because of varying bather load and the slow response from an SWG, manual dosing of chlorine after a soak is usually still required unless it's just one person soaking for a shorter time and the SWG has a boost mode or there is an ozonator.
If the spa is covered, then 30-40 ppm CYA is a good range to shoot for. This is similar to what is recommended for indoor pools though they can be 20-30 ppm CYA in order to more easily have a higher active chlorine level to help oxidize bather waste due to the lack of sunlight. In spas, the water is generally hotter and the bather loads generally have the FC be higher at times so a higher CYA level target of 30-40 ppm is usually better. We don't list spas and indoor pools in the chlorine/CYA chart because they are less common, and for spas as I wrote above it's more complicated but their maintenance is described in the Using Chlorine in a Spa "Further Reading" article in the Pool School.
