Can you elaborate more on this? I've worked with very large codebases in React and Angular and have not seen this issue. I'm guessing it's either because all of my applications were able to hot-reload or we're not thinking of the same thing.
[1] current project is very slow w/ 250kloc (2.5mm kloc w/ dependencies). even seen it be slow on my last project which was only 40kloc.
Hot reloading _helps_, but it's definitely an issue that javascript tooling spends seconds on tasks other languages' tooling spends tens or hundreds of milliseconds on. (The issue isn't just limited to tsc either; just starting the build system can take a decent amount of time with webpack, while make or cmake starts in milliseconds.)