[Proto]

Age has little, if anything, to do with the quality of a given song. Like janfive said, there are such things as instant classics. Good, memorable music should be recognized on its merits, not something arbitrary such as how long it's been around.

I edited my post, reposting

I mean, it would not be the first time for songs that were critically acclaimed in their time to be utterly forgotten later, and pieces who were promptly dismissed as run of the mill to receive universal appraisal in the forecoming generations. The first example would be Bach's Brandenburg's concerto's, which were writen for a contest as the director of a orchestra in Brandenburg. Bach works didn't made an impression in his time, he didn't even rank in that contest. However the Brandenburg concerto's are now one of the most widely performed works for string ensembles. And no one remembers the people who won in that contest whatsoever.

The same with many works that were only given their right stature years later after the author's death. Bach himself, Chopin to a level, Wagner outside of his niche group of followers. On the other hand, few people will remember the works from the myriad of widely loved in their time, but otherwise run of the mill authors from the baroque era outside of Bach, the Scarlatti father and son, Corelli, Verdi, and give or take 20 more.

However, take a moment and consider how far that would restrict things here. If we're saying a song needs to be at least 10 years old, then we're talking about anime that aired no more recently than 1999. Taking as a given, as I said earlier, that anime music prior to the early 90's was largely forgettable, you're talking about restricting our music selection for the greatest anime songs of all time to not much more than a single decade's worth of series to select from. That's not only unfair to the many memorable songs and series of this decade, it's far too narrow-minded.

If you ask me to select between being too narrow minded and restricted in what I can choose, yet my selections being precise and more substantial, or being too broad minded and including a whole new range of music, yet my selections not going beyond my likings, dislikings, and those of my contemporaries, instead of being able to objectively analyse my selections, then I prefer the former. The turn will arrive for the music of the 2000's after all. Waiting for the 2020 is not much to ask. If they are truly memorable they will hold till then.