Being ace is about sexual attraction, not whether you have—or enjoy, for that matter—sex.
Being ace is about sexual attraction, not whether you masturbate or can experience sexual arousal.
Aces have always been part of the acronym, though where we have fallen has changed over time and in different regions. It is both incorrect to say "the A has only ever meant ally" and "the A has never meant ally" (the reason for this is complex)