I would suspect that the increase has something to do with a greater amount of data being held by a greater number of companies, but in any case, things are certainly getting bad.
While decentralized systems can offer better security on the backend, there's still the fact that the gadgets we use to access those systems are highly vulnerable too. It doesn't matter how secure the network is, if the attacker is inside your computer.
To have real security, we need it on our devices, as well as the networks we access with them.