The reason why NFT artwork is worth millions isn't just for a speculative market so another chump will buy it from you at a higher price, but it also has another value. Like all artwork it is used for tax avoidance. The high price of NFTs allows a wealthy elite to squirrel away millions to accrue value without being taxed. They are more handy than a real piece of artwork or some expensive property in London because a digital image isn't vulnerable to physical damage or maintenance costs. It's obvious why this shit is exploding.
I see this a lot on the internet but it's only partially true, like it only happens for the 0.1% of collectors who can afford to slosh $80m in wet paintings into freeports every season. The vast majority of collectors just want to sell their work for more then they paid for it 20 years ago. Return expectations are still wildly inflated, but the whole market actually isn't just a laundering scheme, and most "investors" in conventional art break even at best.
Source: I'm the brilliant but sexy art history major in every airport novel you've read
Oh for sure, only the 0.01% or higher who can afford this do this. You're right that most investors are doing this because they hope to sell for more than they buy, and will have to pay capital gains tax.
I think it's the same with a lot of the art idea, yeah some of it is because of money trafficking and tax evasion, but also its a really inflated market with a bunch of rich people and galleries ready to spend whatever they want and a pretty hard exclusive club to actually get demand in.