The debate is heading toward the safecoin distribution algorithm which is currently not designed, so both sides of the debate are currently theoretical. With that fairly large caveat aside, there seem to be a few points of misunderstanding.
I disagree. The sustainability is independant of new data.
Assume (dubiously) the worst case scenario where no new data is uploaded so no new coins will ever be made available for farming.
There will be some amount of coins available at that time. That amount of coins available will always be decreasing as new coins continue to be claimed via farming. But the amount available never increases because nobody is recycling the ones they have. This is something I think we both agree.
Coins from the pool of remaining coins is issued to farmers at a variable rate which adjusts intermittently, very much like the bitcoin mining difficulty rate. This is speculative, since the algorithm isn’t fully designed yet.
The wiki is old, but since the feature hasn’t been designed it’s still the most relevant info currently available. [Here’s the current idea]:
https://safenetwork.wiki/en/Safecoins_(How_it_works)
The earning rate also takes into account the rank of the Vault, a process whereby the network scores the usefulness of each node from 0 (being the worst) to 1 (the best). The safecoin farming rate is ultimately the result of the network rate, a balance of the demand and supply on the network, multiplied by the vault rank.
The network automatically increases farming rewards as space is required and reduces them as space becomes abundant.
So there is an adjustment mechanism for the rate the remaining coins are issued to farmers. This means that no matter how much the pool of available coins shrinks, there will always be some coins to farm for (even if they are almost impossible to obtain). Thus there should always be some incentive to farm (beside the obvious incentive that farming keeps your own data safe regardless of whether you’re economically rewarded or not).
This does pose a problem though: there’s no incentive for users to recycle coins (which increases the number available for farming). I think is this is the basis for your perspective that farmers depend on users spending their coins for farming to be sustainable. However, this is not true. Farmers only depend on users spending coins for the available supply of coins to increase, but that alone does not necessarily make farming unsustainable. Farming can be sustainable even if the supply of coins never increases. I would be keen to see proof of that being incorrect.
To return to a bitcoin analogy again: Newcomers to bitcoin argue the mining reward eventually being zero will kill the network since miners have no incentive to continue securing the network. The standard retort is transaction fees will sustain the network. The argument being proposed in this topic for the safe network is akin to saying ‘what if nobody transacts on the bitcoin network once it depends on transaction fees’. There’s a bigger problem than no transaction fees - ie there are no transactions! Not to say this isn’t a problem, but is it real? We can only speculate, never really know for sure, despite our best intentions.
See above for the safe network design that also has an adjustment mechanism (albeit currently not a particularly clear one).
I try to debate the ideas not the person, but the lack of understanding of this proposed mechanism really does make it hard. You need to read more about the network. The wiki article is a pretty obvious thing to have read when discussing safecoin mechanics at such length as this, so you can see why a lack of basic background work causes doubt of your intentions. If you really cared, you’d have read more.
Not true. The difficulty remains high until the next retarget. If 99% of miners have stopped mining then blocks will be extremely rare and retarget will take a very long time. What effect this has on users and the network, well, we can guess pretty well but until it happens we can’t say for sure. Just like with this topic.
This means the network would not be autonomous and decentralized so I doubt this path will be taken. But for sure, it’s possible that human intervention may happen at some point, I just think it’s against the ideals of the network for this to happen. (Is that a political shitstorm I see approaching?!)