"It is rarely used "

???

If you walk down the street you will see literally hundreds of people wearing it on their fingers as Jewelry.

BTW - it even has a high degree of utility as Jewelry because it does not tarnish.

Also - it has some industrial use.

And yes, it's highly speculative, but nowhere near BTC.

And finally - it's use as a currency predates recorded history, across countless civilizations and cultures. Which counts for a lot of credibility.