Most module loaders nowadays support all module "formats". RequireJS is a weak comparison because RequireJS is one of the earliest module loaders and attempts to solve the problem in a very specific manner. Furthermore, supporting many module formats is unlikely a perk for any dev team. It just speaks more about "ok I can use this for my system". Most dev teams have coding conventions and stick to one format throughout the project life time. Bigger bonuses to me is being able to consider images, fonts, and CSS as modules. That way my front-end codebase can be fully modular.