Some speculation is destructive; they're not all equal.
I can see that point of view, but in my experience buying up domain names in bulk ahead of legitimate people and businesses, pricing them out of their reach is a systemic problem, not harmless speculation. Not only do they not add any value in their intermediary role, but domain names are a vital part of how the Internet functions as a means of communication. Domains aren't collectible goods or even comparable to land in that respect, because two plots of land can be functionally equivalent, whereas each domain name is unique: if my last name's taken, it's taken.
It's a bit more like if some people decided to (and had access to) reserve and park most phone numbers in a given area code (or a whole country) and resell the rights for $10K each. It's parasitic and interferes with the proper operation of the phone system without added value. The phone is an essential service and these days, I'd say the Internet's close to that. In the phone analogy, I guess regular people would end up getting double-long phone numbers through re-dialing switchboards of some sort, and the few with enough money to throw away would get direct numbers from the scalpers.
Oh wow, that reminds me of my childhood nemesis in the 1980s: rotary dialing! 
Still not a perfect analogy because phone numbers are all functionally equivalent, being 10 digits long, so as long as squatters didn't buy them all, the cheap ones would remain as good as the scalped ones. (Sure there are vanity numbers, but those are gimmicks not affecting length and thus barely improving user friendliness.)
Back on my argument that cybersquatting is a systemic issue, let's not forget the impact on ergonomics for the entire Internet: domain names are probably on average at least 20% longer because of the sheer volume of names parked as "investments" out of reach of companies and content producers. From a macro perspective, every single user loses. (I'm surprised ICANN never cared about that.) Think of all the typo versions you'd need to reserve if you had to settle for "go2e-mailapp.com" vs "mail.com".
(I have a 5-letter domain and already see people typo many variations... Got a cheque for "e-marce" once, I kid you not. How the client got there from "iMars" written everywhere including
on the invoice is a hell of a stretch. Surprised the bank didn't mind.)
So anyway, hoard gold or art as much as you want, but don't clog up an essential service...