This example is just to show that pauses are not in the same class as any other fully managed languages. I haven’t looked at the code to know how much it stresses the garbage collector, but I agree it does seem unlikely to do so.

That said, being able to work on the stack does influence the design of the garbage collector. Throughput becomes less important because you can choose to allocate less, and pause time is more important because latency is harder to optimize. Latency is affected by your whole stack and can’t be meaningfully reduced by just adding more machines in the same way that throughput can be increased.