I think we're getting to the point of personal opinion here, so I'm not trying to argue with you. But the way I see it:

Gus needed to shut off the lights to gain the upper hand. In that episode a few weeks back he didn't just plant the gun, he also paced out how many steps it was from that cable switch to the gun. So he needed to find a way to kick that switch without Lalo immediately knowing something was up and firing. Gus's rant was the misdirection that he needed to make sure Lalo didn't know what was up until after the lights turned off.

There was also, of course, the fan service of letting us all hear what Gus really thinks of Don Eladio, since everyone was a little too busy at the relevant moment in "Salud." I found that super satisfying, but I'll admit it also had a very similar feel to "Well Mr Bond, since you're about to die anyway, let me tell you the rest of my plan..."

But deep down, it's in keeping with the comic-book melodrama that I'm saying has always been there.

Anyway, someone said something in (I think) The Watch podcast about how there might have been some hidden references to Nacho in that monologue as well, but it didn't make sense to me when I heard that claim. I'll be watching closer for that next time I see the episode.