Let this be a lesson that JavaScript is not slow. The DOM can be slow, and downloading large bundles can be slow, and any code can be made slow if you try hard enough to write it poorly. But JavaScript the language is not slow in 2020. When we talk (or rant) about the performance of JS-based apps - running on the web or in Electron or otherwise - it's really important that the conversation focus on the factors that a…
No, JS is slow(ish). The GC pressure alone will kill you. This is fast despite being in JS by simply doing as little as possible (while still meeting the requirements on the end result, which is where the genius lies). The fastest code is no code. No code is fast even with pathologically slow languages/runtimes.
But that wasn't my main point: my main point is that people love to rant about "JavaScript apps" while maintaining (willful?) ignorance about what the actual factors are that manifest as the slowness they experience. Sometimes it's poor usage of the DOM. Usually it's ads. It's almost never the unavoidable overhead of JS cycles.