I hope you do receive something special!
My mother and I just returned from her birthday trip (70-something milestone). We stayed at WL. It was noted on our reservation. At check in, I thought she would be wished a happy birthday and given the birthday button, since it was on our reservation. The CM said nothing and gave us our room info (we had also done online check in.) Upon arriving at our room, we noticed we were given a king bed (kind of odd for mother-daughter) and my mother was not happy with that arrangement.
So I returned to the front desk, mentioned our situation and that it was her birthday, could I have a button for her? The CM apologized, made a button and called to find another room for us. We did not receive an upgrade, our new room was the same category as we had paid for (which was fine).
My mother did not receive a birthday card or birthday call from Mickey & Minnie, things we have received in the past when celebrating birthdays at Disney.
This was also my 3rd stay at the WL in five months, so being "loyal" did not result in any perks.
I think there are so many people celebrating birthdays, anniversaries, etc. on any given day that it is not possible for everyone to receive the "magical pixie dust" they would love to get. Does it happen? Absolutely! But since it didn't for us, we did not wallow in disappointment but carried on and made our own celebration. We were in Disney, and that's all that mattered.