The current state size is ~5 GB. 500 GB seems like the largest that would be feasible in the medium term without requiring almost everyone to get special-purpose hard drives.

So shouldn’t the target be at least 5TB then? If 500GB is feasible for an average node, it should be the expected average, not an impossible maximum.

Also I think you’re significantly overestimating the expected use. Right now there are no storage fees (either explicit or implicit) and it’s only 5GB. Even at 1PB cost per byte would be ridiculously high compared to the cloud storage prices which would prevent waste.

without requiring almost everyone to get special-purpose hard drives

Only validators are paid to run full nodes, average user isn’t going to regardless. Validators and businesses that use ethereum can get larger drives.

Sure, but it also makes spamming the state cost-free for anyone who happens to be holding ETH

No, the true payment unit is not eth but a percentage of the total supply, as 1 ether is only an arbitrary unit. Exactly like shares in a company. Both payment methods are a different way of lowering that share.

The only difference is that paying with lost interest AND not automatically deleting creates the equivalent of a ‘zero bound’ - as maximum allowable storage grows with the total supply.

So unless hardfork/gas limit like/ increases are going to be substantially smaller than increases in the total supply, the explicit payment model makes no sense, as it adds complexity for no gain.

IF they are going to be, then all that additional complexity is there only to prevent a few percentage points of growth at most. Is it really worth it?

the status quo is incentivizing the emergence of second-layer rent markets, see http://gastoken.io

Yes, that’s because gas fees are conflating performance and storage costs. Locking eth solves that.