Bitcoin is better than paypal when it comes to security. There's 2FA in Bitcoin, signed message, email verification, etc. And the person you're transacting with cannot secretly dispute his payment before 180 days. The only advantage of using Paypal over Bitcoin is that there are more online shops that accepts paypal than bitcoin
Bitcoin itself doesn't have 2FA and email verification. It's either included in the clients itself, or related to certain wallet services and exchanges online.
Other than that, you're right, Bitcoin doesn't allow scammers to cheat on people by charging back money where the selling party ends up with the losses.
That's why stores, online sellers, people doing side jobs, and what not, should start accepting Bitcoin as an optional payment method. Better safe than sorry.