Blockchain enabled transaction processing where the parties to the transaction don't need to trust each other, as long as they are only transacting in goods stored on the blockchain. Once you get into the world of one party having to physically deliver something the other party will use, you're back to the problem of trust.

So until all software runs on the blockchain, no, as long as you still need to install it onto your device, you need to be able to trust the delivery network. You certainly don't need a central authority for that. Normal desktop devices work perfectly fine with people relying on PGP signatures in common Linux distros or something like Chocolatey on Windows and Brew on Mac. But you don't need a blockchain, either, nor does it add any value.