I dunno, I’d have to look through the lore shit again that I never much cared for. I guess because it’s not practical to punch behemoths like the Icon of Sin to death. The real reason is obviously just for gameplay.
Well in most versions of the anime and the manga he makes that mistake, but then puts 2 and 2 together after Vegeta explains that all Saiyans can transform like that. In the Ocean dub (from what I remember at least) he just thinks Vegeta did it.
The power needed to actually kill someone is by far the most inconsistent thing in this series. Certain characters will have the plot armor needed to survive shit all the time. Freeza should've beheaded Goku by accident after taking his KHH for example.
Sometimes the dialogue bubble just doesn’t have the little arrow bit that tells you who’s talking in situations where it really should. I can’t think of an exact example right now but you probably get what I mean. Like, the characters are drawn in the panel, so you can have the dialogue bubbles...
I've done it a couple times, long time ago. I took notes when I'd watch really bad shows because it was fun to talk about with people (mostly GridZero) after.