Pros and cons of making hero image clickable

On the meeting with website stakeholders I was asked why not make hero area clickable and lead to promotion page in addition to CTA button leading to the same promotion page?

Since it never occurred to me that one could want to do that I found nothing better to say then "It is not how web works". For me it is not what people expect and it violates POLA principle, but is it really?

I'm curious what are the pros and cons of clickable hero images?