Ultra violet protection (UVR) a clear coat paint (isocyanate polyurethane) provides the colour and base coats with protection, and usually has UVR protection added in the final coating; this tends to migrate towards the upper level of the clear coat (this is why it?s important to check how much of the paint surface you are removing with an abrasive polish)
[EDIT- added] Carnauba waxes - contrary to popular belief and / or marketing do not contain natural UV protection; the oils (usually silicone in most products) make it very difficult to add the UV inhibitors.
There is no such thing as a permanent UV stabilizer, it a matter of physics, not chemistry. Polymers (acrylics, etc) resist UV degradation very well due to their structure, they are somewhat immune and absorb very little ultra violet radiation, and hence UV energy does not damage them
So the use of a paint protection that contains UVR protection is very important to avoid clear coat failure