My frustration with the system

Wanikani doesn’t fix this because they don’t need to. A user already solved this:

Because WaniKani alone is a product for users that don’t want customization. One of the reasons why Anki doesn’t work for a lot of people is because they mess up with their own customization. You could be different, or maybe not. Still, you can learn 2000 kanji and 6000+ words in 1 year and 1 month (max speed). Do you really think that’s slow?

Still, they offer an API key for programmers to be able to create their own customization, turn it into a script and offer it to other users.

Because a user already solved this.