Well, it doesn't break the laws of physics, so it already more plausible than wishful thinking FTL tech.

Another scenario I could envision would be if we get a good handle on the tech to live and work in space to the point that living on a massive space habitat is indistinguishable from living on earth.

Then we hollow out an asteroid and build a mini biosphere. Give it a push with a massive space based array of lasers, and off we go to another star.

The argument goes that unless humans become an interplanetary species they are at risk of extinction through an asteroid impact, a bad plague, nuclear war, climate change, etc..

As long as these resources can mined from the Earth, nobody will mine for them in space. They are virtually useless to the Earth economy.

But do you know who would benefit enormously from asteroid mining? People who are already living in space, the moon, space habitats or Mars. The problem of course, is that no such population exists at the moment. The only way to break this chicken/egg conundrum is to massively invest in getting people to live in space. It seems like a lot of money in the short term, but over the long term it would pay for itself many times over as more and more industries move off the earth. Then we can figure out how to bring those resources back down to earth.

So someone has got to go first.

Yeah, I don't get this. If they are after the people with money they mostly live in Cities where the sky is so light polluted that nobody even looks at it anymore.

In low earth orbit this thing will zip around the earth super fast. So if you wanna see it you will have to look at an app that tracks the orbits of satellites around the earth. Not exactly convenient.

This is more of a Marketing PR stunt for bragging rights. They will have to run ads on TV to remind people they are advertising in Space.