In Wall Street's eyes, bitcoin is just another asset that they can make bubbles upon and earn lots of fiat
Not everyone thinks it's just another asset. Some of them are privately buying and holding for long term use because they see a potential scenareo where Bitcoin becomes a new standard of digital payments.
And at some point it will become plain obvious that anyone with any available fiat to invest with should do so by putting at least a small % in Bitcoin. Bitcoin will become the most exciting thing to have in one's portfolio.