NACK
It's easy to say let the market decide. But markets don't exist out of nowhere. The marketplace must be designed so that the incentives of participants are aligned. Bitcoin acknowledged this reality from birth.
This proposal creates misaligned incentives. It asks node operators to host arbitrary data that is of no value to them without compensation. The question of whether there is sufficient incentive to operate a node is already somewhat shaky. This proposal would make it worse.
And this is a good point to remember, to all those who lean towards laissez faire, as I do myself: Satoshi when he created Bitcoin made opinionated design decisions about the network. It is appropriate for Bitcoin devs to continue making opinionated design decisions about what the network is for. We need to make sure that the devs make decisions that are supportive of the principles of sound money and financial liberty. I don't see how turning Bitcoin into a decentralized storage layer supports that goal.
If people are interested in decentralized storage, which I believe is a worthy goal, they should start a different project. Perhaps bitcoin can be part of that solution as the way to incentivize hosts... but don't put it directly on the blockchain please.