Every product manager job is different. Some are easy and some are hard. Right now, being the product manager at Boeing who is responsible for the 737 MAX jet would defiantly fall into the difficult category.
The reason that this would be such a hard job to have right now is because this airplane has experienced a set of disastrous crashes. In October, Lion Air Flight 610 crashed just minutes after taking off from Jakarta, Indonesia. It was the first fatal accident involving a 737 Max. 189 people died. This was followed in March when Ethiopian Airlines Flight 302, involving the same Max jet model, also crashed minutes after takeoff, killing all 157 people on board.