Look at that Wall of Jericho. I ain't reading all that.
Hey, go to hell, and take your sh*tcoins with you.

You really are clueless. Proof of space is not a proof of work. That's the whole point. When you work, you consume energy (a lot of it since the work can't be trivial) and the point is to not do that, since it's terribly inefficient. Well, there is still work involved as initial processing is required and it has to be expensive enough to ensure that you store the results instead of recreating them every time you're asked to prove you still have them. So, hypothetically, it can be operated as a proof-of-work system. However, when set up well, all rational participants should choose to expend storage over processing. And therefore proving there is storage being taken up. Although you cannot be certain storage is actually used. There could be a lunatic at the other end.

You're trying to do something very sensitive (like processing payments) without having to trust the people involved. The basic problem is an agreement on what is the truth, the reality - what do you believe. You're trying to make it too difficult for anyone to manipulate it and, say, erase a payment from existence (rewrite history). Which inevitably means some kind of resource is needed. I think Microsoft might have an interesting idea where they use human activity. You can't buy humans in the way you can buy GPUs.

Really, this should put more pressure on HDDs than SSDs. Simply because they're cheaper for any given capacity. Some might get used for caching but the bulk should be cheap (but durable) storage. SSD would only make sense if its lifespan would compensate the higher price. But it would still mean more capital being tied up, even though it would be cheaper long-term (you would need to account for the cost of money for a complete picture). I would have to check the details but when it comes to dedicating SSDs to this, it might be perfect for cheap flash with few rewrite cycles and slow, primitive controllers. If you store once and then just read, read, read, high-end flash or controller is just a waste of money. It would be more of an archival-type system.

Yes yes,
now we have dozens of practically useless cryptos that use GPU´s, so next comes the useless cryptos using SSD storage.
But thats not enough really, we must also invent a "proof of pixels and refresh rate" that makes use of your monitors pixels and refresh rate.
And after that, there must be someone inventing the "proof of environment" where you have to go to your next gas station, buy sh*tloads of gas and just burn it in a barrel.
I hate this world