You’re overstating things. First, 100k objects is for very complicated games. And even then that’s 10us per object. “Nanoseconds” is the wrong order of magnitude - it’s closer to 10s or 100s of ns and a bounds check is cheaper than that typically and amortized across all objects. Bounds checks are unlikely going to show up unless you do a bounds check for each element. And most of the time it won’t be there with idiomatic rust and you’ll need to sprinkle unsafe in a handful of hotspots at most for perf reasons. Also most games made don’t have the same requirements. I agree the ecosystem isn’t there yet. But also, gaming is the least important industry because safety there is an after thought.

As for finance, you’re hyper focusing on HFT which is only part of what they use c++ for.

And again, I think you’re being a bit overly dramatic about the overhead Rust imposes or how much “unsafe” is require to recapture the performance.

As for aliasing, you’ve got it backwards. C++ loose aliasing rules means that it can’t enable optimizations that generate better code. Rust’s stricter aliasing rules means they ask llvm to compile with strict aliasing which generates much better code because the compiler can make assumptions that aren’t possible in c++ unless you explicitly force it to (and in those cases safety can be impacted so in practice no one enabled strict-alias in a c++ codebase which we know because llvm has bugs in that code path all over the place that Rust hit and had to fix which it is).