I disagree. Just look at the people in this thread asking how to install it. In a VM you will mimic what you will eventually do, and installation is an apt-get or yum away.
If someone is learning off of, say, Windows, their experience may possibly be quite different to what they will experience if they run this within a VM.
Just look at the people in this thread asking how to install it
They are talking about how other installation methods than Postgres.app can be difficult. Which is exactly my point: If you're on Mac and you want to get started with PostgreSQL easily, Postgres.app is the way to go.
If someone is learning off of, say, Windows, their experience may possibly be quite different to what they will experience if they run this within a VM.