If you're looking for a non-surgical way to induce a bleeding ulcer, try altcoin trading for a while. You will be in the hospital within 6 months if you can last that long. Shitcoins are unpredictable, and the market for most of them is so thin that it's impossible to exit your position without tanking the market (if you bet big enough). I seriously doubt more than a handful of people make their living full-time trading shitcoins. There are more people who probably lie about doing so.
I think you have some bad experience in trading. But you have a point. Me too don't believe that we can have a stable profit for daily living in alt coin trading. There price is volatile. Maybe in forex trading you can get that stable income. Alt coin is very hard to predict and so many factors to consider especially the devs of coin. Hahahha.
Its really hard to earn a living with this because trading needs time and effor and sometimes coins you desired to sell are not moving as you expected and sometimes the price will suddenly deeply drop so thats why i dont see any angle or any people really earning a living for altcoin trading, maybe OP is expecting to much profit from it that enough to earn a living.