Bitcoin has never lost in the long run.
What exactly makes you think so? Bitcoin is currently down ~60% from its ath ($69k), so how can you claim it has never lost in the long run?
What you mean is that historically Bitcoin's price moved in cycles, with each cycle bringing new ath, but, as the things currently are, you cannot say that it has never lost, as that's simply incorrect.
Also, the belief that the price will keep moving in the same pattern forever is naive. It's simply not possible for it to move by a similar percentage each cycle, as everything has its limits.
In 14 years of existence and development, bitcoin has had impressive growth, and anyone looking at it must be envious. But that cannot guarantee that in the future things will still happen and history will always repeat itself in such a simple way. If bitcoin investment is that easy as long as long term holding is sure to be profitable, then I will sell all my assets to invest in bitcoin without worry, LOL.
Like what is happening, when everyone knows bitcoin will increase in price after the halving? Is it that simple? Are we all going to get rich so easily?