Magic UI uses tailwindcss first approach to vastly simplify the code and make it portable. With tailwindcss, our stylesheets went from 50-100+ lines of css per component to just 1-4 lines of tailwind.
Magic UI was built to be compatible with shadcn/ui and the registry system from day 1. It's safe to say magic ui would not have had the distribution and reach it has today without the foundation of shadcn/ui.