However, I don't think falling off the wagon ended up being a bad thing for me really. I was very early on in my Japanese learning journey when I started, and at level 28 I was far better at kanji recognition than I was at any other relevant language skill—I couldn't really speak or understand anything yet I was learning how to read "攻撃". Stopping WaniKani then let me focus more on listening practice and led to my skills balancing out a bit.
Overall I believe WaniKani is a great tool, and well worth the money. But it covers just a small slice of what it takes to learn Japanese.
As a coda, I'm only now getting back into dedicated Kanji study again. However this time I'm following the book "Kanji in Context"[1] and using Anki to ensure recall. From a slightly more advanced perspective, it's all the more rewarding when you get to a character you know you've seen many times but never really got to know explicitly.