My autobiographical memory has always been terrible. I think aphantasia might have some part to play, but I think there might be a couple of other factors too...
Firstly, I have quite severe alexithymia; so when an event happens to me, it can take quite some time before its emotional impact hits me and even longer for me to make sense of what the feelings are. When I recall autobiographical memories, they seem very abstract, almost as if they were things which I'd just been told about or read. They usually contain very little emotion, so I wonder whether that is because of the separation in time between the event and the emotion, so that they don't get recorded as a single, unified memory of the event.
Secondly, my sense of time is atrocious at all scales, from judging how long I've waited for a bus to having any idea when any particular event took place in my life. Even putting autobiographical memories into the correct order requires a lot of working out, and this often leads me to get confused about who else might recall the same event or the order of cause and effect when remembering things.
_________________
When you are fighting an invisible monster, first throw a bucket of paint over it.