Even if this were the case, and I wouldn't be surprised, it's still misplaced blame.

> Knowing your user is important, no matter what level you're at.

I agree, but it's absolutely ridiculous to expect a junior dev to make excellent decisions on this. Software development is a massive industry with no prescribed methods. It's not like these folks are going through a residency before getting the job. Even if they went to uni for CS those programs don't teach these skills.