The problem with many people is that they think that if they invest all their money in cryptocurrency they will become rich very soon. But unfortunately the opposite happens and they lose all their money and remain in debt. But this is not the problem of CEX or DEX, it's the problem of people who can't manage their money properly.
Exactly. You can't lose if you only put a small amount of coins in an exchange. Unfortunately, most people believe CEXs are reliable custodians like banks so they leave their coins and forget about the rest. Convenience goes on top of everything else, right? Because of this, we should expect another major crypto exchange from collapsing in the future. This simply can't be avoided.
At least, it's not that bad. CEXs may be a constant victim of hacks and closures/seizures, but they often have good liquidity and unmatched performance. DEXs are safer but they have low liquidity and are often expensive to use (due to increasing network fees). Which exchange to use is entirely up to you. As long as you act responsibly, there should nothing to worry about.
