Why would a billionaire being surrounded by young woman be a red flag? Being a billionaire is enough to explain their presence without any hint of coercion.
It's unprofessional at best but as we know know, many of these girls were sex trafficking victims and underage.
It's also known that Epstein's island residence was decorated with pictures of underage nude girls and a giant nude painting of Ghlisaine Maxwell. So yeah, I'd say there are quite a few red flags there.
As far as nude pictures and paintings, were they clearly underage and non artistic? There's a lot of post hoc reasoning by those who want to spread blame around that doesn't stand up to scrutiny.