Why would you want to though? It takes at least an hour to confirm (~6 blocks) without a third-party and the fees are getting super high (costs around $13.50 / 30624 satoshis per transaction to get reasonable transfer times). So unless you're transferring a large amount, you're better off using a third party that can just hold all the money and flip a bit in their database saying the money is moved.

Bitcoin takes an hour to confirm, there are other cryptocurrencies that take much less time.

Bitcoin also has the fee problem, and more recently Ethereum. Other cryptocurrencies like Bitcoin Cash with larger block sizes don't have the same transaction fee problems.

Cryptocurrencies are still relatively new. Most of the problems are being solved and the technologies are improving rapidly.

True. But you can’t really buy anything with it.

Which means you need to cash out to fiat $$$. And then you need 3rd party authorisation while jumping through all the KYC hoops.

PayPal accepts cryptocurrencies now, so I don't think it's fair to say you can't buy anything with it. Also there are decentralized marketplaces like OpenBazaar, which are still pretty new too.

But why does that require a specific monetary value for bitcoin? And doesn’t this apply to any cryotocurrency?

it doesn't. People just like to exchange it for real money. There's no real need, everyone just still prices things in USD instead of btc. Once btc has around a $20T market cap, it will be much less volatile.