I mean, we're talking about the value of a business. Boston Dynamics is more of a research lab. They don't really have much in the way of revenue streams, customers, products, etc.
Some of the scientist and engineers working there might invent/discover what could be the most significant thing in human history for the next hundred years. Leading to a fabulous amount of wealth creation. But there's no guarantee the company financing all of this will be able to capitalize on that invention.
That's a lot of ifs. If people there invent something important; if the company sees the true value of the invention; if it is marketed in a way that makes money; if etc...