This is not totally true. We have seen so many people have their a wallets hacked and money getting stolen. Cryptocurrency is mostly about taking control of one's funds including it's security. Once the wallets are compromised, the money is not secure.

I also know of fake coins/less secure blockchains that suffered 51% attacks leading to losses. So people should stick to the most secure cryptocurrency which is Bitcoin Avoid shitcoins like Bitcoin diamond, Bitcoin Gold, Ethereum classic etc.