Of course it matters because you matter.I'm older than you(don't want to tell my age) and it's never too late.

I can relate to that dumb wall.I had that too I didn't call it a dumb wall though,I called it a concrete wall.I couldn't get past it no matter how hard I tried.It was like if I tried to think too hard to remember too hard,etc. there was a wall blocking my access.The wall was there for a reason though.It was there to protect me and to help me survive my painful past.In therapy though I was able to break down that wall.It took a long time and a lot of work but eventually there was no wall and integration happened.

I don't remember right off hand if you're in therapy or not.I suggest it if you're not.Everything behind your dumb wall is most likely too painful for you to face and process on your own without outside help.That's what the protection is for(wall/alters).

You're definitely not dumb.The seperated knowledge and experiences,that's basically what DID is.