Trading is too complex an activity, because there is no one clear algorithm that would act the same way for everything. Therefore, every trader tries to create their own strategy that will work for them.
Most of them experience losses in trading because many people think trading is easy and even underestimate their knowledge about trading or even think they have mastered everything about trading properly. Even though it is true as you said, trading is something very complicated and all strategies cannot be applied to everyone because it all depends on our suitability for the strategy. Maybe lastly, every time you trade, keep learning, even pro traders never stop learning about trading and use failure in trading as an experience so you don't repeat the same mistakes.
That is very true, they see people do crazy 100x leverage trading and make a lot of money from nothing and share it on instagram or tiktok, and they try to mimic the same thing and end up failing. It's quite clear that we are talking about something that is very rare, but when tens of thousands of people do it, every single day, it's only natural that you will see thousands of them every week.
This brainwashes some newbies that they are capable of making that much money with trading, and they should join, which only results with them not making that type of income at all. I believe that we are going to end up with a greater return eventually, we just need to accept the fact that it will take a while before we could get there.