'Activist judge' is indeed a term in the English language, but what does it have to do with this case? There are 'drunk airplane pilots', but does that make the pilot of the plane I'm going to board a suspect?
I think of it in an engineery sense - if the edge case is possible, it will happen.
Maybe that works for software engineering, where it's a good idea to pause a release in case someone uses scripts to send a shitload of bad requests to our API and crashes a server because of our bug or whatever, but I understand that that doesn't work 1:1 with the real world, where it doesn't make sense to not have the aviation industry until we perfect self-flying planes.
So, assuming all those eventualities, why shouldn't we just put you to death now?
To spare you the rhetorical exercise, the answer is because we don't punish you for the things you might do, but only punish you for a) the things that you have done, b) that we can prove, c) beyond a reasonable doubt, d) in a court of law, e) before a jury of your peers.
No, not at all. This is closer to what the parent was saying
By that argument, someone will:
* beat his wife - true
* murder an enemy - true
* shoot up a school full of children - true
* commit arson - true
* jump bail - true
* evade arrest - true
* die in a hail of bullets - true
You see, all these things do happen. The parent is not arguing that because something is possible any one individual will do it. You're arguing a very different thing.
I think we're getting a little sidetracked here. What the grandparent wanted to say was just that the corset of laws that binds a judge might not be as tight as you think; hence e.g. activist judges.
I think my point stands, which is that not every possibility is an eventuality, and we shouldn't assume that to be true without a willingness to accept a very bad panoply of preventative measures masquerading as corrective measures.
That said, whether or not an activist judge allows a presumptively lawful merger to occur is hardly a hill worth dying on. We have remedies for activist judges through an appeal process. Where an appeals process is not available after the merger, we have remedy for anti-competitive companies through regulatory influence, regulatory agency, rule of law, and a court system to back that up.