Why to act "professional" if amateur approach works brilliantly too. Shooting to film is another story.
I belive he gets it from his teachers? old photographers who do act professionally, because they have shot to film 20 years?
Maybe. It is quite common to learn that you shouldn't photoshop, you shouldn't do this and that, this and that is important.
Thing is, most professionals will use RAW in the end. Some used dias film in the day, but negative was more common, and you did things to that in the dark room.
What people seems to misunderstand is that yes, while learning to expose, it is nice not to photoshop all the time. That just lets you get lazy with your exposure. With JPEG, you have less working room in the files, so you end up having to learn to expose the hard way, a bit like dias, only JPEG gives you more room to recover.
But, as another teacher told me once, crap in, crap out. Photoshop can't help you if you're completely lost.
As for light meters, I see their use, but I fail to see how they are crucial or even important.