Actually that is what it says.
“. All persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United States”
Exactly "subject to the Jurisdiction thereof" has been contorted to mean that just because some tourist (or, in this case, someone who sneaks into the USA SPECIFICALLY to drop a baby to gain U.S. Citizen BENEFITS), is NOT subject to the "Jurisdiction", which was meant for INHABITANTS of the USA, NOT FOREIGNERS.
To think a vacationer can drop a baby in the Country, just to gain Citizenship automatically, doesn't even pass the smell test.