For example in crypto, market makers are commonly making 100% return. You haven't heard of these firms and they aren't interested in your money.
Market makers usually do quite well for themselves, but are capacity constrained: they can earn stellar returns on tens of millions of capital, but maybe not hundreds of millions or billions. You probably haven't heard of most of these firms and they would prefer to keep it that way.
of course if you want a public example, look at RenTec. They are unique in generating eye popping returns with such a large amount of capital. This is extremely uncommon. However generating comparable returns on 500-1000x less capital is significantly more common. These returns often don't compound tho, as they are severely capacity constrained.
But I’m a retail investor, and will almost certainly remain one— Not only do I not have the training to come up with these strategies, I don’t have the knowledge to judge the veracity of anyone claiming to sell them to me either. I’m content with my suboptimal portfolio that I don’t have to think about more than once a year, and have more important things to spend my time on.
Equities are different because their connection (however tenuous) to actual earnings gives them a very steady long-term uptrend. The hard part is just staying in during a crash so you don’t miss the recovery. Half of S&P 500 returns came on its ten best days.