Let's end this then DL.
Piccolo D casually destroying cities.
Here's another explosion from Piccolo D.
Looks like this on the anime. That's far above mountain busting, that's almost the size of a mountain range.
Here's Piccolo D stating his power and that he could destroy the world. Bear in mind, he is weaker than Majunior and Popo both.
And this is an island bust.
And most importantly, Goku defeats the Piccolo from aboves. Yet when faced with Mr. Popo....
So what we know for certain is that the tailed beasts will never even hit Mr. Popo. At this point in the series, Goku's movement was far beyond any character in Naruto. If you need proof of that, go by the Tao Pai Pai scale. He was Hypersonic+ and he is SLOWER than Mr. Popo!
Not to mention, Popo can basically insta-transport to any spot on Earth without even zeroing in on someone's ki. It doesn't matter if we've never seen him punch anything. We know that he has the durability to take hits from Goku, so that pretty much tanks anything the Narutoverse could ever throw at him. But it doesn't matter. Even if Popo used just his fist, moving at Mach 10 would turn a 1 lb object into a number I don't even wanna calculate right now. Either way, more than enough to knock a Bijuu's head off being that someone like A can rip off their horns with peak human levels.
Seriously, I hope you don't continue to try arguing this because it's not even fun.