There are some advantages and disadvantages of using a non-free trading course. People who learning will tend to study harder since if they know they are taking a paid course, they paid for it to learn so they more become serious to think that they will not waste their money. On the other hand, while using a free trading course, you can say to your self "I can't study it since I got it for free, so no need to worry"
That applies to some of the users, usually some of the subscription based paid studying apps will have a limited time for which the app will be accessible and the learner has to make sure to put in everyday effort to cover a portion so as to not waste their money.
But I guess in trading you dont need to be an avid learner, nobody is going to take an examination of your skills rather these will end up as life skills to handle your money in the market. So both type of courses can work nicely.
The bottom line remains that if someone has the willpower to learn something, then nothing can stop them from learning it. However learning trading does not equal to trading success, point to be noted.
There are some online courses that can really help you get in track but they're a rare gem online as the most popular online courses are just clickbait or just a quick cash grab for the creators of those courses, you're right that it's all theories but at the same time we also need to do some applications on those theories.
The internet is made for clickbaits only. But on paid platforms, it is usually less. The videos on youtube will have some content to it rather than just clickbaiting. The learner needs to block out the BS that every shill spews and take in only the needful information.