I think you misunderstood what they are trying to say, that they mean that cryptocurrency trading is more like gambling and therefore it should be classified accordingly because it is a high-risk investment as gambling is an attribute of the nature of investment and not something in itself.
Self-regulatory organization CryptoUK and crypto exchange Kraken have slammed a recent report from a panel of British lawmakers that suggested crypto should be regulated in a similar vein to gambling.
Generally, though the classification varies a lot you still need to verify identity before trading and these platforms need a license to operate in the UK.
Personally, I see that the United States has a leading role here, and once it establishes a clear organization in the United States, I believe that many countries will start following the same approach to reach a global organization.
But in any case, it is unlikely that Bitcoin will be classified as a legal tender, but rather an asset or a commodity.