Interviews check for fit first of all, and especially in a buyers market the point is not to solve the assignment, it's to blow it out of the water.

It's meant for the person for whom it's ideally an afterthought. Tough reality.

> …which is totally understandable… if the hiring manager had communicated that.

I agree that the hiring manager could have handled it much better, but as a rule: If at any point during any hiring process you feel like you need to spend even close to a full time week of work on anything without being very explicitly told so, you are wrong.

I am a hiring manager and we do take home homeworks. I fully agree that this is a key piece of communication. I always take the time to tell candidates that although they have as much time as they want, we expect 2-3 hours of effort at most, to be respectful of their time. Without that, take home problems would seem predatory.