poetchic advertising scam via Stocks app

I responded to an ad displayed through the Stocks app on my iPhone, only to realise a couple of days later that it was in fact a scam.

Does Apple not take proactive steps to ensure scams are not occuring on their devices?

This web site 'poetchic.com' was already being highlighted as being a potential scam, unfortunately, I didn't check before I placed an order.