AGREE in a general sense. i guess, as I try to understand the mindset, I'd say 3 things:
1) Sydney is obviously a very rare breed in that she appears to really enjoy showing them off, and not all women are like that. Maybe Sophie and the others that drive us nuts aren't wired the same way and don't want to always be showing them.
2) Sydney is a famous actress and I think there's more of an "aura" around it every time she does it (especially knowing it can only be rare in movies/TV) vs an Onlyfans model who could do it every single day if they desire.
3) Sydney gets paid very well for her acting and showing them even briefly. While Onlyfans models would get paid well for that first nude photo set or video and some after, eventually, as I said, they think the buys would decrease. Another reason for this would be the line is always moving, right? So now they don't show nips we want nips... say they show nips... after a while (if they even continue to keep showing them) it becomes, show vag or show your guy playing with them... the demand will always keep increasing so if they don't do that stuff people will keep being disappointed.