You can't dip into the documentation for the one thing you're trying to do, you have to spend time reading a large chunk of the documentation, then going to forums and such to try an understand the history of how that one thing you're trying to do has changed over webpack's history.
Then 5 months later when you're doing it for another project, you have to re-read all that documentation again because one other thing is different.
Compare that waste of time and effort to:
A developer is now unavailable and you are taking over the project. The project uses a modern build-system/module-loader/etc... You need to change one thing to the way to project is built.
You don't have to learn an uber nested spaghetti config file that looks like a domain-specific language. You just read the miminal configuration the previous developer left you and now you know what to change, or how to add the one thing you need to do. You've now saved days of work.
I just replaced Webpack with Vite, in a 2yo React project, with relatively standard webpack config (scss, fonts, assets copying, minify etc). I was able to remove 24 total devDependencies packages, including the whole of babel and its related ones, bunch of webpack plugins that broke our build on every packages upgrade (e.g. to Webpack 4, then again for Webpack 5) etc etc.
We now have nothing to do with babel, hard-to-understand plugins that someone added since it was solving a build error, nothing to do with webpack, just 1 almost non-existent config file, instant HMR, and 3x faster build...
You were meant to rely on sourcemaps to get something on your debugger, but despite using the latest Chrome and developer tools at the time, I could never get it to work to actually debug sites.
I know Rollup, Vite and etc had a much easier time providing an easier developer experience because they rely on the browser's native ESM support, but I never could understand why webpack decided to mangle the code so badly.