Optimizing web fonts is crucial for branding and user experience, as inconsistent rendering of these fonts can cause unintended shifts in layout. The font-display property allows developers to control the behavior of web fonts by setting it to various strategies such as block, swap, fallback, optional, or auto. Ensuring consistency with fallback fonts requires careful selection and adjustment using CSS descriptors like size-adjust. Reducing download times is achieved through resource hints like preconnect and preload. The next/font module in Next.js automates many font optimization tasks, including downloading the web font at build time, adding a fallback font, automatically preloading the font, calculating necessary measurements, and improving performance and user experience.