First, the article says because the U.S. Air Forces stated Takeshima, not Dokdo in its maps in 1950s, Dokdo was and is Japan's territory.
It is very unreasonable ground for any claim.
If the claim is held true, then, the opposite should be also true meaning that the islet should be the Korean territory because there are so many other records and documents that state the islet as Dokdo, not Takeshima.
In addition, the source of information, namely the U.S. Air Forces is not an authoritative body when it comes to the naming of territory. There are other official bodies in the U.S. that at least recognize the disputes between Korea an Japan by stating both Dokdo/Takeshima. There is no reason to put more weight on the U.S. Force.
Last but not least, Treaty of Peace with Japan (San Francisco Treaty) signed on 1951 had several revision during preparation. The first draft and later drafts till November 1949 did state Dokdo as the Korean territory, but took it out from the version in August 1950.
The signed final treaty says, "Japan, recognizing the independence of Korea, renounces all right, title and claim to Korea, including the islands of Quelpart, Port Hamilton and Dagelet."
This article clearly says "ALL right, title and claim", and takes "the islands of Quelpart, Port Hamilton and Dagelet" as examples.
It would be so foolish to interprete this as only the islands of Quelpart, Port Hamilton and Dagelet are the ones whose right, title and claim to be returned to Korea.