and especially this, proves that Yusuke is far more then a mere island buster. you can downplay all you want, but it strongly implies, through multiple people and sources, that they are potential lifewipers, or even planetary threats. but i suppose you'll claim they're all mistranslations and hyperbole huh?
They are indeed capable of lifewiping/threatening the entire planet, but it is no different in how many Naruto and Bleach characters also are potential planetary threats if they keep on destroying and killing things at the same rate over a very long period of time. There is no evidence that they are capable of blowing up planets or razing the entire planet with their single most powerful attack. It also doesn't help that their actual feats during the Chapter Black and Makai arc where they are hundreds of times stronger do not support their planet-level hype.
The best thing that S-class demons is given in DC based off their hype is small country-busting capability, because they have already been smashing durable mountains in shockwaves alone and the country that's being threatened to be destroyed likely refers to Japan which is a small country.