if they did that we would have to wait for them to put more scenes more monsters and scenes that is gonna make us wait for year
its just the way with small/indie games. A lot of one man, or small teams posts a beta/alpha and see if people are interested. It's kinda how some devs like Poppy Playtime found huge success despite my personal opinion that the story is kinda bland.
Sometimes you or your team can only have so much passion or money to continue development. You also want feedback for future development.