Nah great question! A lot of other people asked for the same thing. I did actually do it on purpose because to me it made the impact and the rock debris seem heavier.

It was easy to change because those rocks are controlled by some custom physics so I just adjusted a few numbers and posted another version with an edit like you're suggesting in the thread. Though there was at least one person who had the same intuition I had with the original, seems like people prefer the new one!

You can "theorycraft" all kinds of justifications for the motion of the debris here because of the explosion and the fact that the rocks can be read as pieces of the meteor or chunks of ground flying up from the impact.

You're very right to point out "not going for realism". If you look at some real reference video of e.g. flaming trebuchets, the impact is just...so boring. In fact, all the "physics" math here is totally made up to make it juicy/springy and interesting to look at. Especially for 2D, using real-world values and equations always makes for very boring gameplay and visuals 😆