I don't recall any issues suggesting Angel's costume is intended as camoflage.

All said pretty good examples, I would say, of why we should look upon those variant renderings of Angel's costume as blue, rather than black, as something not at all uncommon in comics: mistakes.

If I understand this discussion correctly, both Storm's black (white highlighted) costume and Cyclops' black (blue highlighted) are purely comic book colors, i.e., conventions of the medium that are very difficult and sometimes impossible to translate to another medium. Their costumes are colored the way they are, that is, with different highlights of the same basic color, because in comic books they look really good, to speak plainly. As a matter of comprehending what the coloring convention conveys it's not trivial to grasp that Superman's hair is black or that part of Spider-Man's costume is black, despite or rather because of the blue highlights. Nonetheless, I'm not so sure it's more important than simply for taking comic books as they are.

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I don't recall any issues suggesting Angel's costume is intended as camoflage.
*****

And as a ten year old, I never thought that it was supposed to be camoflage.  As a ten year old, it just made sense that the color would be blue, it made a lot more sense than the red one, thats for sure.  Twenty-three years later, this is the first time someone seriously brought up that it should be something other than the blue that ten year old saw.