Why would he stress about a theoretical inefficiency that has very little effect on the finished product or development process? Especially one that could be rectified in a weekend if needed? The game industry is usually pretty practical about what it focuses on from a performance perspective with good reason. They don’t build games like they’re demosceners min-maxing numbers for fun, and there’s a reason for that.
I also wonder how many people who sing the praises of an HTML file with a script tag hosted by Nginx or whatever have ever built a significant website that way. There’s a lot of frustrating things about the modern JS landscape, but I promise you the end results were not better nor was it easier back before bundlers and React.