I didn't mind the one on Rannoch, really. It was basically pointless, but it didn't hurt anything. If you don't fire it, everything continues as normal. The only point in firing is to see if it does anything or just for the hell of it.
But the one on Earth was so stupid. It was boring, and it didn't mean anything since no matter if you hit one enemy or all of them, they get swept away by fighters anyhow. And besides that, like you said, this was when we're having all these (honestly fantastic) conversations with friends we've spent years with. The "storming heaven" and "gift" conversations REALLY did not need a pointless pew pew pew interlude.