The decentralization means that we can remove the inefficient intermediaries (banks, lawyers, notaries, clerks, courts...) and replace them with computer hardware.
So ether can only do one instruction a second, try buying a house and see how much beurecracy is involved. Try buying one on the other side of the globe and you will be burried by documents. That is inefficient, not ether.
If that house was listed on a public blockchain you could make the exchange in minutes and pay next to nothing in comission and you could trade that house globally.