I'd say, more so, the distinguishing factor between an investment and speculation is that an investment is used to facilitate a business process that could potentially create wealth whereas speculation is a bet that something of value will be worth more at a later date.

It's like, I think that lithium is gonna be short in the near future. It's really useful stuff. But I'm not buying kilograms of raw lithium to hoard in my garage, I'm investing in the companies that oversee the element's mining, processing, surveying, etc. And maybe looking at commodity options in the short term, but given what happened there with aluminum...

Crypto can play a similar role.

Real investments have a return derived from capital. A house, for example, can be rented out for money. Or a business can earn profit and distribute it to its shareholders. You can try to buy and sell houses like people did during the RE bubble for profit, or try to buy and sell stocks like a day trader, but these are still fundamentally different from an "asset" which has no means by which to generate a return on its own.

You can buy goods and services with Bitcoin. It's just another currency. Do people claim that forex is not investing?

Yes, all the time. It's clearly speculation (in the technical sense)

Not really though. You can buy a few novelties online and there are a handful of places that accept bitcoin, but realistically it is not "just another currency", it's an IOU for usable money.