From the use cases you can tell they basically manage the risk of holding crypto for institutional clients while providing an easy to use interface, that's definitely worth a ton of money if done properly.
Are you implying that a company that processes hundreds of billions of dollars in transaction volume is thinking of acquiring this company for the hype alone?
I would expect a company of this magnitude to have done a proper research before paying out half a billion dollars for an acquisition that's not based on hype alone.
Sometimes I have the same thought—people know what they are doing and wouldn't just fork out money on the basis of hype—and then I remember that similar stuff seems to happen quite often. Even relatively recent examples – Yahoo! and Tumblr, eBay and Skype, News Corp and Myspace, even Google and Nest.
From the use cases you can tell they basically manage the risk of holding crypto for institutional clients while providing an easy to use interface, that's definitely worth a ton of money if done properly.