Why would he answer it? It was literally someone doing his job for him. If anything, he would have applauded.
I mean, if his job is
literally only to destroy things, as such, not to destroy things specifically injurious to the order of the cosmos, then you're right, but it undermines your next point...
To be fair, that's only what he says his reasons are. He's a god, he could know things and act on that knowledge, then cover it up with a silly or nonsensical reason just to ensure that his reputation for random destruction continued to spread. People who are panicking at the mention of his name are likely pleasing to him, after all. Please keep in mind that not all characters speak the truth at all times, especially those who are powerful or who have secrets.
...Because he behaved fully consistently with acting in a petty manner, and with being concerned chiefly with things that really don't have much to o with the good of the universe. Like, y'know, food, petty slights, getting to see a super-saiyan god in action, and so on.
It's like, either he can be playing eleventh dimensional chess and cultivating a reputation for fearsomeness while at the same time targeting things that need to be destroyed for the good of the cosmos...
OR he can just be generically in favor of widespread destruction and satiating his own personal whims.
Can't be both.
There's still no reason it would be the Enemy. There's an advantage to going to hell that doesn't exist with the Enemy. I don't believe the qm would add an insta death option even if they didn't warn us about one.
Put this way.
I don't think Poptart would include a vote option that secretly drops us in front of the Enemy to get insta-gibbed.
I DO think Poptart MIGHT include a vote option where, IF WE PLAY OUR CARDS WRONG, we get dropped in front of the Enemy and insta-gibbed. I'm trying to avoid such a scenario even arising.
Does anybody else think the Enemy's actions are strange? If the thing was willing to kill an innocent planet to take out the Saiyans, I find it odd they balked at systematically obliterating each galaxy. Popping in to a system and detonating it's star wouldn't have taken long. I mean, if Broly could kill a galaxy, any idiot with SSB power could do it trivially. He can screw with Sight, so presumably foresight from the gods is out as a means of predicting which specific system he's going for, making Beerus and Whis setting an ambush a non-starter unless they get spectacularly lucky.
What's more, if he was strong enough to kill Goku and Vegeta, presumably working together as SSBs, then him being able to at least keep up with Whis and Beerus to the point of being able to escape to the next system over is completely plausible. Unless he's like Babidi on steroids and his ability to jump between systems is shit compared to his direct combat ability. That would explain why he wouldn't do that, though it wouldn't explain why everybody was so scared of him if running away was a perfectly viable strategy, since he's clearly not on the level where he can erase universes at whim like Zeno'o in this scenario, or else he'd have done it to erase any chance of the Saiyans coming back.
The only explanation I can think of is that The Enemy's got some kind of grudge against specifically the Saiyans, and harboring them is enough to give a planet an execution, but not a whole galaxy or universe. Of course, he could simply be like if Beerus was completely morally bankrupt and went out looking for good fights, only blowing up Earth as 'punishment' for dashing his hopes. The Vision didn't give me that impression though.
Well, it's entirely possible the Enemy
does specifically have a grudge against saiyans, or against the lineage of Goku in particular.
But basically: the strongest thing the Enemy is known to have survived is a fight with Super-Saiyan Blue
Gohan, and the self-destruction of same. We don't know by what means the Enemy survived that, though from our vision we know he seems to have been largely unharmed by the experience. The Enemy also hacked his way through several SSJ2's and 3's, and a god ki wielding Piccolo, but all of those things are weaker than Gohan was.
Basically, the Enemy may or may not be a threat capable of taking down the gods. It's hard to be sure from my point of view. But he's a big enough threat that he could cause a lot of damage if he felt like it, and the fact that he hasn't eaten the universe or anything over the past 300 years is a strong hint that they'd rather fort up and wait him out than try to go after him actively.