you should not be a 10x engineer or whatever, you should be focusing on the vision and ideas and emotions that make your project interesting and beautiful and touching. some of the greatest indie games of all time have absolutely nightmarish codebases because the creator was rightly focused on the player experience
once you reach the point where you are working with multiple developers touching the code or it's a project you'll be working on for years, a lot of standards like good/consistent variable names/formatting/commenting, using design patterns, and keeping things relatively maintainable/decoupled/reusable so people aren't spending too much time going "what the fuck is happening here" is worthwhile
