Yea that was a foul ball, if were in keeping with the MLB batting average analogy of the humor in Ragnarok. However, in Korg's defense he's likely seen a lot of world destruction and heard tales of even more. This was not an Eternal making that joke and it didn't stray from the general sincerity of the character from the onset. .$02.
I as well really enjoyed Thor 3 and it's a shame at this point it's not brought up but the visual aesthetic of that movie and the incorporation of the Kirby pulls, are THE MOST comic book of ANY of the previous MCU movies. You can turn it on, turn the sound off and visually it looks like a silver-age comic. None of the other movies have that going for it. Wakanda had it's own great visual palate but Ragnarok looks as if it was pulled from the page.