More or less that’s right. They’re a good step toward seeing pictographs as phonetic characters.

When I first starting learning Japanese I took an intensive 7 week course. We learned Hiragana and Katakana in one week, though it took longer to really make that knowledge long term available. I forgot a lot of it after completing the course, but my first year living in Japan helped restore it all!

Now my kids are learning kana and my oldest kanji. The state of the art here is still drilling and repetition. FWIW this website is cute, but without learning the characters you have to rely on verbal instruction, so as an experiment it only works after learning the Kana.