I do my Anki reps and sometimes watch vbijin, but I find myself listening to Japanese music more than anything. I get that song lyrics aren't representative of real sentences, but surely there's still things of worth in there. I like Tatsuro Yamashita, Jody is a banger.
I have touched on this topic in several places of the guide, but I'm going to reiterate everything here since it's easier to read one Q&A than the entire guide.
Listening to Japanese music is not going to hurt you, and it can even boost your motivation if you find it enjoyable. Moreover, reading and analyzing the lyrics can help you learn new vocabulary. By listening to music in Japanese you can learn new, unique and cool words that aren't commonly used.
As for myself, I occasionally listen to Japanese music. It can be satisfying to understand the words in a foreign language through listening, especially when it is a song you already liked before you started learning Japanese, and now you can enjoy it even more.
Among people who are doing AJATT music is considered a supplement. It's not the most effective way to learn the language. There are things you can learn from music, I just don't think it is very efficient. I almost completely stopped listening to music after starting AJATT. To this day I do it only occasionally.
There are some legitimate drawbacks to using music for learning Japanese compared to other immersion sources. It contains unnatural speech, and it is difficult to hear the lyrics through music. We tend to mishear lyrics even when we listen to songs in our native language. Depending on your current level of comprehension, your gains from music may be very small. Without reading the transcript deciphering the words can be a problem.
Songs contain unnatural sentence structures, grammar, word choice. They tend to use more "poetic", uncommon words. Sometimes if a word can be read many ways, they choose to sing the less common version. It's pretty different from everyday speech.
Because in general it's harder to hear what people are singing in songs
compared to everyday speech,
it's better to choose more comprehensible materials such as
TV shows, dramas, movies, or anime for immersion.
Among these options, anime is a great choice as it generally features
clear voices of professional actors and standard, natural sentence structures.
Although it may include 役割語,
which can be a bit annoying, it's not a significant issue.
If you prefer to avoid
you may want to consider watching j-dramas,
but keep in mind that even these may be affected if they are adapted from manga or light novels.