Bitcoin will never gain mass adoption as a currency, that leaves it as a "value store" - and the only people buying bitcoin are suckers buying bitcoin from others in the hope that they can in turn sell it to a bigger sucker down the line.

It's because that is the primary "use case" of Bitcoin right now as Bitcoin is even worse at being at currency than an investment.

Bad price stability, slow transactions, high fees under any amount of load, bad privacy, terrible adoption, etc, etc

The overwhelming majority of holders of Bitcoin disagree with you.

It's a garbage currency - fees are too high, transfers too slow. It's a garbage technology that encourages wanton energy wastage. Its only "value" is as an investment.