... having used it for the last 4 years to try to memorize vocabulary in certain languages (Spanish & French, recently started Chinese), I think it's a base layer... (much like how Bitcoiners like to talk about BTC's Blockchain). Reasons:
1. I've tired of it. I need a layer that makes me excited to use it.
2. I've found it far-far less useful for learning other things than rote vocabulary memorization. It needs a layer that makes it easy to store and "pull up" everything I need to know.
That said, I don't want to sound like I'm looking a gift-horse in the mouth. Anki truly is a great piece of software, and my sincere thanks to the devs.