Как много нам открытий чудных... Из tvtropes:
"Originally, Hideaki Anno intended to use a piece of the Polovtsian Dances for the opening, but the studio came to the conclusion that it would be too confusing for the viewers and thus had "Cruel Angel's Thesis" made to replace it with modern J-pop".
Так что опенинг "Евангелиона" мог звучать так:

Только покороче)