...only 6.2% of a highly developed country like the US of America own Bitcoin, which seems unreasonable among the crypto community who rely on the Americans for Bitcoin to be mass adopted quite fast around the world.
I thought people were relying on the unstable parts of the world for mass adoption.
There isn't any need for Americans to adopt bitcoin - they still trust the dollar (which has been gaining value against other fiat currencies since 2014), they have a solid economy and low unemployment. And their banking system is sound (it got fixed properly after the 2008 crash).
Adoption is more likely to happen in Europe due to problems with their banking system and the potential break-up of the euro. (If the euro looks like breaking up, watch for money to flow into dollars, yen, pounds, swiss franc and yes, bitcoin).