Until now, I probably agree with you that cryptos are some kind of gambling because it's so hard to predict any price or movement, that even real good analysts are wrong almost all of the time
With all the guessing, and predicting, and waiting on what will be the price this time to the next minute or hour, hodling is really somehow like gambling. In gambling, you don't really know if you will win or lose; and same here while hodling. I mean, one don't really know how much cryptos like bitcoin will cost. That explains all the price prediction threads here in the forum. However, they also have difference in the sense that, in gambling, it depends on either luck or strategy but in hodling, it needs more strategy and wise judgement on when to buy or sell.
Indeed, gambling and holding crypto have a lot in common when before decisions, everything is just a prediction, no one will guarantee what will happen after their decision, however, holding cryptocurrencies as a form of gambling is probably at a higher level, depending heavily on strategy and skills while casual gambling games rely almost on luck. And the obvious result is that when we rely on calculations, the chances of profitability are higher when we only rely on luck, smart gambling is always a good choice