Why not? Nobody processes at that quantum because no demand has been shown for the service. Blockchains are inherently less efficient than the databases modern financial systems run on. That tradeoff is core to the technology.
For every transaction a bank processes there's obviously a fixed cost. Once you account for all the costs relative to them in a given year and divide that number with the number of transactions in that same year, I doubt, given the margins of a given transaction, that a bank can break even on 1 cents transactions. That's assuming that the tech the banks use as of now does not improve by magnitudes in a couple years.
This is a strange argument. Visa's costs, per transaction, are demonstrably lower than Bitcoin's. Specific banks and systems may be more or less efficient. But fundamentally, the trustlessness that is a blockchain's selling point comes at the cost--by definition in proof of work systems--of efficiency.
With blockchains it's mostly about operational expenses. Now, bitcoin transaction fee might be currently high but it is a problem of this blockchain implementation and not with blockchain per se.