You must have all three to trade successfully and they're written in order of importance.
You must also learn each aspect in the order I have written them. You can be a master of trading psychology or money management, but if you don't have a technical edge you won't make money.
95% of retail traders never overcome step 1, this is why so many fail.
Overally, first off, what makes a good trader is profitability. It doesn't matter if one has acquired all the skills that you listed there or not. Win rate is the only thing that can prove that one is successful or not, not a mere understanding of those terminologies.
While I acknowledge that the three items you mentioned – TA, MM and Psychology, are of high necessity to achieving wins in trading, trading psychology or emotional control should come first.
Trading will test your patience. If you don't have the ability to overcome the necessary emotional control you're bound to make errors. Sometimes, traders have their technical analysis and Money Management techniques right but still end up not being profitable. The reason is because they're yet to get a firm grip on their trading emotion. Without a control of this, trading will always be done in panic. It's bad.
I agree that anyone can easily understand any theory and memorize it quickly, such as learning analysis techniques, designing strategies, and conducting trade planning in just three months or be very fast. However, that does not mean that person will become a good trader who can consistently make a profit or earn more profit than their losses.
The most challenging aspects of trading are patience and mental resilience, which require long-term cultivation. As I mentioned in my previous post on this forum, emotions such as greed, anger, frustration, panic, and others can significantly influence decision-making and often lead to serious issues.
I would only suggest that if your mindset is not yet well-formed, and if you cannot manage your finances, never become a scalper or a day trader. It will be mentally draining, and honestly, you don’t have to trade every day to be a good trader.