DApps are smart-contracts are a very clever way to carry transactions and operations in a trustless way.
However, they are still vulnerable to hacking and exploits, caused by details left unsolved in their code.
Paypal has their source code away from the public, which makes them less likely to fall victim of exploits, smartcontracts on the other hand, need to have their code exposed for everyone to see, for the sake of decentralization. Of course this makes easier for hackers to study and find ways to exploit Dapps and SC.
So I would not say they are "more secure" yet, since only takes a mistake or a flaw on the code for all your money to be gone. It has happened in the past, for example, with pickle-finance.
https://www.nasdaq.com/articles/defi-protocol-pickle-finance-token-loses-almost-half-its-value-after-%2419.7m-hack-2020-11Once your money is gone, there is nothing you can do to recover it, unlike Paypal, where you may have a chance, due to the centralization.
I'll give it some more time for the Dapps and SC to be more secure, tho.
Developers are always learning and it is just matter of time for these protocols to grow more secure for users, in my opinion.