Anki definitely works for memorizing the hell out of vocabulary and I also don't regret completing WaniKani, although I would probably choose an Anki only approach if I had to start over. At some intermediate level I stopped looking at the mnemonics completely and just did as many reviews as possible until it stuck.

I also got a lot of value out of wanikani even without completing it.

I tried and failed several times to get started with Anki before having success with Wanikani. The key diffentiator for me was the learning step. Anki is great for remembering things you were taught or learned outside of it, but using Anki to learn new things is very much a learned skill that Wanikani holds your hand through.

I have N2 and am working on N1 now, and feel I still have a very long way to go before getting to CEFR C1. Now I only use Anki with the yomitan and takoboto integrations to quickly add any words I look up, which seems to be working well.

I agree with you, but Anki is a generalized flashcard SRS memorization tool, not specifically made for learning Japanese, so it's not within my area of critique; I'm thinking of apps similar to Duolingo. It works extremely well because it helps you memorize very efficiently. One of the few applications that will indeed boost your learning by a lot. Anything requiring manual input rather than a simple Again or Good button choice tends to be worse. Any Anki deck requiring manual input as an answer should not be used.