I've never had ear training, but I can learn a piece by ear at least 2x as fast as reading. Why?
I am a hobbyist pianist, and I've known how to play piano since I was 6. Even young, I was able to learn songs without having sheet music to the point that I can't learn music without a recording with it. I try to strengthen my sight reading, but when I play pieces before listening to a recording, rhythms are off and accidentals are wrong. The piece sounds foreign to what should actually be played. When I play the recording and hear where my mistakes are, I Instantly got it. It's memorized and I rarely need to reference the music again.
TL;DR: Why can't I read as well even though I've been able to read for a long time? I can play more complex pieces by ear, but reading them is a major chore. Do I need to start reading easier passages? Thanks in advance for advice.