Yes, it's an anki replacement. I found adding/modifying cards programmatically was a nightmare. I also wanted to add new features, like having ephemeral cards that disappear after a few reviews (the use case was translation of chatgpt-generated sentences - knowing myself I'd just unconsciously memorize the answer and not actually go through the task of translation so I wanted to automatically get rid of those cards after they outlived their useful lifespan). And in general I didn't want to be constrained by someone else's software.