There is nothing weird about our rendering. Everything comes down to draw calls of which there are thousands. Many blocks use a merged mesh, meaning combined with others of the same category in their chunk to be draw in a single draw call. Combining does add overhead of making that mesh each time a block is added or removed. Many other blocks are props, which have their own renders, models, LODs and mats, which makes a draw call and because of instancing many of those of the same type can also be rendered in a single draw call. Those do not have the overhead of combining and get to use LODs to be culled at a customized distance based on their size. Everything is tradeoffs.
Turning off any type of draw calls would of course make FPS higher, but the whole point of the video in video games is to render things otherwise you would be staring at a black screen.
Sorry, no "true" fire zombie in the burnt forest. We already have the burnt zombie, but I believe there is more fire on him or her (hard to tell) 🔥.