None of this is specific to cryptocurrencies or even money, people do this with stocks (esp penny stocks), precious metals (look at all those "Buy Gold!!" videos), and collectibles (I still remember the beanie baby craze of the late 90s).

This is just gambling, betting that you'll cash out before everyone else, but after the price has run up.

But that's not "how all cryptocurrency works." Yes, cryptocurrencies are valued based on supply and demand, but many aren't actively speculated on and are used more as a currency. For example, Monero isn't attractive for speculation because mining is unprofitable and exchanging with fiat is banned or difficult in many areas. It's great as a currency though because transaction fees are low, transactions are fast, and it has a bunch of privacy features. Bitcoin is more attractive, but not as much for gambling because volumes are too high to get crazy spikes. So you end up with longer ye term speculation in Bitcoin like you'd see with individual large cap stocks. Bitcoin isn't going to 10x overnight, but it's also not going to drop 90% overnight either.

Like anything else, pick carefully, and ideally don't gamble.