I think the whole concept of “immersion” is given too much attention. I could sit in a room with Japanese people and have no clue what’s being said. I could stare at Japanese text without knowing how to read it. That’s not a very good use of my time. In my opinion, immersion is really just struggling to make headway in the current of information flowing your way, and I think it’s the struggling part that makes it useful. It’s not very pleasant and it is tiring.
I agree that it’s better to learn basic vocabulary and grammar, then try to use things like graded readers and other materials designed specifically for beginners before trying to tackle more advanced content.
I’ve been doing some form of “immersion” by trying to read a novel and I’ve only made it a couple paragraphs into the text after more than a month.
It’s boring and it takes a lot of effort.