Online casino design evolved as smartphones became the main way people play....

https://shanesexpertthoughts.capitaljays.com/posts/why-do-casino-sites-feel-closer-to-mobile-games-than-to-old-gambling-sites

Online casino design evolved as smartphones became the main way people play. Developers prioritize mobile-first user experiences to fit quick gaming sessions on the go. They make game catalogues easy to browse with simple taps and clear categories