That is true, a lot of games can be played easily with the WASD + Mouse keybinds. Not unusable by any means, but it can be frustrating for people who get thrown off by the on screen prompts corresponding differently than what their controls actually are.
Their developer, Redline has a known history of mental illness, and he banned many people for having competing games in their library, leaving bad reviews, criticism, or just challenging him or calling out wrong or shady practices.