We also used to write code in low-level languages, and system designs were simpler compared to our current approach of writing a lot of stuff in JS and using Electron everywhere, having a huge dependency tree and in general - optimizing for fast development rather than efficient runtime.

Having said that, optimizing for perf is rarely worth it because people don't usually care, and when it is - you can often make the biggest difference by figuring out why some step requires O(n^3) instead of O(n) like it should and fixing that, rather than rewriting the entire stack to get some 10-20% improvement...