My mom always speaks admiringly of how well my son expresses his feelings. I always had tremendous difficulty talking about what was going on with me; she's told me that once during a very bad time she broke her own strict rules about privacy to read my diary but it was no help at all. I didn't even write about my feelings. Possibly I didn't even understand them myself.
Son has always been encouraged to understand and express himself, with additional expert guidance since he was 3. Today I noticed an unexpected benefit of this: when you have words to understand your own feelings, it's much easier for someone else to explain their feelings to you. Telling him "please be quiet because your dad is stressed" brought out frustration and stomping. Reminding him that noise is one of the worst things when he's feeling stressed brought peace and a loving apology.
He absolutely has empathy, no question of it. As with so many issues regarding disabilities, it's just a matter of the right access.