The English word comes from Latin, septem = 7, membris or mens = month (like menstruation).

In the Roman calendar the months are:

1. March
2. February
3. May
4. June
5. July
6. August
7. September
8. October
9. November
10. December

So the order of the months was more logical, and a Roman would naturally understand that September, October, November, and December read as literally the seventh, eighth, ninth, and tenth month respectively.

I basically constantly have to manually correct myself over and over that for example September is the 9th month, to look for the number 9 even though when I read "September" I am reading "seventh month" and my brain automatically wants to look for 7.

I think most people would not relate to my experience of the months let alone how upsetting this is to me, hence I consider it a "small hill" to die on, lol. But it's a very big hill in my world!