Complicated topic with lots that could be said. Keep in mind if this is a Series A company, they most likely do not care about your ability to actually develop

Complicated topic with lots that could be said. Keep in mind if this is a Series A company, they most likely do not care about your ability to actually develop their tech. More likely they are looking to enhance their credibility by adding your name to their sales pitch. (Especially in “AI” businesses which are mostly snake oil.) So you need to consider your reputation and whether you want to attach it to this venture. Very rich people trying to convince you is a good sign - will you still have a good relationship with them if this startup fails? Will they help you find a soft landing? On the other hand, very rich but bad at convincing you - to the extent that you’re asking a random message board - is a bad sign.