Python gives you other interesting ways of going fast (a lot of high performance plugins for numerics, Cython, and so on), while Ruby is a higher level more expressive language IMO, so you have more ways to shoot yourself in the foot more powerfully.

But in my experience it does. I've built platforms in Ruby that handle north of 1K reqs/sec with bursts of 10K reqs/sec on moderate hardware, without needing to setup a whole cluster of machines that crunch on poorly-performing code.

From my experience, getting the average execution time per render from say 0.1ms to 0.01ms, and especially reducing allocations and GC pressure has a big effect on 99% percentiles, and consequently on the cost of compute.

Saying because we use Ruby we don't care if it's slow or not is in a way dismissing it as a viable platform for writing reliable software (because performance is part of reliability).

To me, you can use Ruby to create systems that have very good performance characteristics, and still benefit from developer happiness. The two are not contradictory.

Just the thought of comparing Rubys execution speed with Rust is pointless. They are completely different languages and has their own use cases, if you care about performance, Ruby is not it. I don't think the author intended to oppose that either

Edit: Another honorable mention, look at Delphi in its prime, millions of lines of code, compiles in under 5 minutes.

Yo dawg, I heard yo and yo dawg like yo-yos so I put yo dawg in yo yo-yo so yo can yo-yo yo dawg while yo dawg yo-yos, dawg.