I fully agree with you. It is clearly possible. It is only a question of learning - learning both the theory and the practice. This is why I always say that the key to success is not in the trades, it is in the trader and the preparation work.
The trader MUST develop a professionalism. There is no place for revenge trading, over-trading, FOMO, and all the other common errors that emanate from our human characteristics. But that does not mean one has to de-humanise, it just means learning the discipline. One can only imagine the discipline and training needed to fly and land an aeroplane, or lead troops in dangerous territories, or sail a small boat in heavy seas, or carry out a surgical operation. No-one can do any of these without the training, knowledge and discipline in procedures - trading is no different. People just have to realise that and work at it - it is not impossible, it is not even difficult.
It is just hard to do alone, with no formalised guidance and learning, just through one’s own mistakes, the hard way.