Even if you're one of those people who believes the highest levels of performance require manual memory management (I'd disagree, but whatever), you'd do well to consider the performance of real-world GC against performance of the Arc/Box/dyn/clone-heavy "high-level Rust" [1] [2] that people and LLMs usually write.

Maybe you can write a carefully-tuned arena-and-slotmap that beats the pants off any GC. GC doesn't have to compete against P99.9 systems programming excellence. It has to compete against an endless soup of Arc, Box, and clone, and it will win this match without breaking a sweat.

[1] https://hamy.xyz/blog/2026-01_high-level-rust

[2] https://llogiq.github.io/2020/05/30/hi.html