It is not easy to hire great product managers — whether you hire those with product management experience or not. The key as you said is looking for people who are product junkies and product curious.
That said — someone will do themselves a disservice if they avoid hiring product managers without product management experience. The best product managers you want to hire have worked with a team that has shipped meaningful products you admire. And they can walk you through the process of how they supported the team and company to deliver the product and what they learned. They can articulate how this fit into the overall company ambitions, the ambitions of the founders and CEOs and also what they wish they had done better in hindsight. The most important though is references from the team and whether they want to work with the person again.
Hiring PMs straight out business school isn’t great unless / until you have a good training program and mentors to learn from. This is why it is often bad for startups but ok for larger companies which have training programs. They often become some of the greatest PMs and go to smaller companies too. Many of my friends are great examples.
PMs don’t need to be technical but it sure helps when you can sit with engineers and have enough sense of what they are talking about. You can be technical without knowing how to code however.
Anyway — I think this article may lead people astray but not hiring existing product managers. It is an art not a science and a skill that the best product leaders get better at over time. But that only happens if they keep working on and shipping good products