I performed a search on the Ancestry.com database of World War I veterans and found quite a few hits for men born in 1917. This time, the problem is not with Ancestry.com.
When I reviewed some of the 1917 birth entries in the database a while back, I noticed that that was the year that was on their registration card. The post in this image indicates the year on the card is clearly 1917.
Transcribers are told to transcribe what they read--and this card says 1917. Of course draft registrants for World War I could not have been born in 1917--which goes to show that sometimes you must be careful entering in certain parameters, particularly when those details could be wrong on the original record.
And if readers do not know why World War I draft registrants could not have been born in 1917, then a review of either your math skills or history knowledge is in order.
Sometimes the original record was wrong in the first place and it's not the fault of the person or firm who created the index.