The plugin was only used when the `NG_BUILD_PROFILING` environment variable was used. The environment variable also enabled the Webpack builtin `ProfilingPlugin` which is retained.
The builtin plugin provides a chrome events JSON output which can be loaded in Chrome DevTools and allows for graphical timeline views of the build.
The `speed-measure-plugin` is also currently incompatible with Webpack 5 which would prevent the CLI profiling support from working with Webpack 5.