Software is slow because of bad design, not slow languages
Rewriting a program in a faster language often misses the largest sources of latency: unnecessary work, serial operations, database query patterns, and poor data flow. The article argues for profiling and redesign first, with language rewrites reserved for genuine CPU-bound hotspots.
The Lobsters discussion pushed back on the article’s broad claim that most software is I/O-bound: commenters pointed to CPU-heavy browser, graphics, and ML workloads, and noted that memory use and vertical scaling can also make language choice matter. That makes the useful takeaway narrower than the headline: measure the actual bottleneck before choosing a rewrite.