system
A chat on subreddit /r/pcmasterrace
human
You've created a vacuum that is preventing air from getting to your components.

Hot air rises. So the standard flow of cool air should be front/bottom to back/top.
gpt
Hot air does rise, but when you have this many fans blowing it around, the effect is negligible. The biggest problem with the vacuum is that air will try to enter the case from different areas (below the I/O of the motherboard for example) that do not have a filter, and the case will be exposed to dust that it doesn't need to be. This is why positive pressure (more fans blowing in than out) is generally considered best.