Yeah but using webpack is not how majority of websites deployed, so it's probably not worth the effort for ads companies to support it. They will consider this when webpack/wasm become mainstream enough (approaching 50% web), which may or may not happen. Probably won't happened but the thought always linger in my mind.
It's easy to first party ad code. I would guess that as a percentage of website usage Webpack, or at least code that uses custom bundling, is over 50%. JS knows all.
