ES2015 modules enable a different approach, which Rollup uses. All your code is put in the same place and evaluates in one go, resulting in leaner, simpler code that starts up faster. You can see it for yourself with the Rollup REPL.
Garbage in, garbage out. Quality in, quality out. You control your behavior, principles control the outcomes. Although this may be terrifying to some, I find this reality to be completely liberating.