I agree with some of your given points and it is really important for someone to be knowledgeable about trading before going into the market and risking a lot of their money. But this knowledge can't be gained using demo trading as it won't involve the emotions and the psychology of the person trading whereas trading real money does.

I'm not saying to risk all of your money in trading but it's good to first use 5% of your trading capital to trade for learning. It's  not much and will give you so much knowledge about the importance of discipline, emotional control, and psychology.

 If one uses a small amount for their learning in the Market it will be more beneficial and knowledgeable than any of the paid course available. And to learn the basics YouTube is full of courses.