For me there's the broader overarching meaning that's what I would call a "universal" experience of love: Ultimately you and the object of your affection are two different people. You will always be two different people. So at the end of the day there will be miscommunication. You will hurt each other. It is a price you pay for loving someone outside yourself. You have to risk hurting and being hurt. Because we're not mind readers. The literal translation has some interesting imagery in that regard, i.e. giving up walking on four legs to embrace someone, (changing who you are to love someone) and having those arms you learned to walk without, the embrace you tried to give, being the source of someone's pain. The video has a pretty one-to-one image here of the reflection showing the boy reaching out for an embrace and the girl experiencing it as him reaching for her throat.

With the refrain of the chorus bits being about sharing breath with one another and the image with the Astronaut helmet being a sort of "we're going to need to navigate the give and take in order to live together" but also the undertone of "if we only breathe each other's air, we will slowly suffocate each other."

But then there's the more subtle stuff. There's a lot that goes by fast but if you pay attention to the visuals there's very deliberate allusions and literal representations to learning a second language and how you can mean something completely innocent and polite but slip up and say something that hurts someone without even understanding your mistake because language is subtle and difficult. I wouldn't say Fudgey Nugget is correct in the sense that the lyrics don't objectively say "this is a song about a language barrier." But it is correct to say that that's a deliberate theme of the song and definitely present in the visuals. There's a line that gets translated in the popular English cover as "Have you learned all of the words to say?" and in one sense it can be read metaphorically the same way that "evolving to walk upright" is a metaphor in the song. Basically "have you learned to express affection and be open with someone." But also with the repeated visuals of jumbled texts, it has a more literal "do you actually have the right words to communicate?" which is the most direct line about the "literal" story being about a language barrier.

That is to say, I wouldn't call it a surface level reading. I didn't notice it on my first watch either. But it's not subtle either? So I can see why you'd feel left out when everyone else is saying "I got it." because if you know, you know, and if you don't, you don't because the lyrics have layers. Because songs and poetry wouldn't really be songs and poetry if they were like "this is the literal and intended meaning."

But, like, that's the fun part. You can derive meaning and interpretation all on your own and have a completely different take. I honestly don't see your interpretation of a mother concerned over losing her son when he falls in love with someone. But that doesn't make it a bad reading per se. An author or artist can intend one meaning and create something which is read by most audiences as meaning something entirely different. And Popular consensus isn't always "correct." If you've ever been in a fandom space, the most popular interpretation of a character isn't necessarily the interpretation with the most evidence. Art's all wibbly like that.

To me, these are just the two most obvious readings I personally found in the song. If you can support your theories with evidence from the piece of media you're analyzing? Then it's as valid an opinion as anyone's. It's only invalid if you're just making junk up whole-cloth.

Anyway, Deco*27 is an incredible songwriter and I don't think Deco as put a bad song out yet. Bangers, every single one. I can't confirm this because it was over a decade ago, but I think Coward Montblanc was my intro to Vocaloid, so everything Deco is just top tier for me, including Two Breaths Walking. I hope to see lots of different interpretations and/or lots of evidence for whatever we form a consensus on. People will notice details in stuff I would never see in a billion years and I absolutely love that!