You are kinda wrong about the 2020 halving.
If I remember this correctly, the Bitcoin price went up to 35K USD in the beginning of 2021, which is several months after the halving. 35K USD was the ATH price back then, but the price broke the record and increased to levels above 59K USD in the spring of 2021, which was the biggest ATH in the history of Bitcoin. You are counting only the highest ATH after the 2020 halving, not the ATH that was before it.
Yes, many people think that Bitcoin is moving in cycle and that there's a price pattern, but this pattern won't continue forever and we shouldn't rely on such predictions all the time. I also believe in a 2025 ATH, but there's no guarantee that it will happen.
That is the only thing people have at their hands and that's why they are doing something like this. There is no argument that they won't be able to do it, we should consider that as a possibility and should be making as much profit as we possibly could from whatever we can predict.
I am not saying that all those predictions are right, but what is the other possibility, not trading at all? Just making up stuff? Sell or buy according whatever you feel like that day? None of that works, having a data historically is still better way to do than all those methods and that means we are going to end up with something that will profit people on the long term as well. If we are right, this is a good way to invest based on the past.