Most marketing is evil.
A product hype wave can be an engineering apathy wave.
When product sells something that is not thought through, not real, not worked on and iterated on, without talking to engineering, they are building a hype wave that is an apathy wave for engineering. The engineers would like to say how messed up this is, but product has already made the unforced error, so why bother.
A great product person will be open to feedback and change patterns based on how engineers feel. I have yet to meet a great product person.
Good marketing is when the data and evidence shows that something is far better than it is perceived to be. The marketing works to close that gap by making the otherwise boring look flashy and highlighting the real impact relative to other things. Good marketing can steelman their opponents and still win.
Evil marketing (almost all marketing) is when a company is stretching to be something they are not. They need to build hype and sell whether or not there is a real product to do so. They would get blown over immediately if compared to opponents realistically, and so the only way to win is to distract, over sell and under deliver, and follow that quickly by the next distraction so nobody notices.
This sort of marketing can be seen at the individual, team, and company level. Think iPod vs Zune, or iPhone vs Nokia windows phone. I can tell from experience, I was at the windows phone launch event in person, and it was all marketing. When you actually hold the device and try to use it you could tell it was purely vaporware with no real thought or data behind it being a good product.