Looking at other recent subsonic airliner developments, Boom is on an impossible timeline, and the order is a useful PR stunt for United that gets them regular attention with every news article. They won’t ever take the plane. And United has the nerve to say this will be a green aircraft because it can operate long thin routes - supersonic aircraft are never “green” and many of the advertised routes are served anyways.

This video from Real Engineering does a great job covering this topic:

Supersonic Air Travel Return?

The conclusion is not much has fundamentally changed since the Concorde, engines for supersonic flight have made little progress, this paper aircraft still has no engine to power it, the advertised fuel savings are mainly from slowing the airplane down, and it can’t even fly the Pacific routes it advertises.