For an example, Dungeon Crawl Stone Soup is a game that took the complexity of content-filled roguelikes (commands for every key on the keyboard, multiple mode-switches for many commands, layered tileset mapping, etc) and added a beautiful and easy-to-understand and accessible mouse-driven UI and graphical tileset to it, without harming pure-keyboard accessibility.
It's completely possible, it just takes some effort.
It's completely possible, it just takes some effort.