This is not correct. I am not an AAdmiral Club member, but I know they have reciprocal agreements with at least 2 or 3 others OW lounges including Qantas Clubs. Canadian Empress Lounge used to have such agreement with AA too when they were in OW.

For what is worth, being a former Oneworld Sapphire and a current Star-Alliance Gold, I feel that Oneworld's lounge program is better. I never had to buy any club membership b/c mine is complimentary with Canadian Plus status and not only I had access to ALL Oneworld Business Class lounges(excluding few notable First Class lounges unless traveling First Class). This is also valid even traveling within the U.S. Furthermore, not only I have access to AA Admiral Clubs, I also get two complimentary drinks automatically at the bar! I really like their clubs in Honolulu and Chicago. Oneworld has much less exclusions than Star-Alliance in terms of reciprocal lounge access. Very often, the best lounges (i.e. the ones at the home hub of each airline such Air New Zealand, All Nippon Airways, Varig and etc.) cannot by used by Star-Gold status or RCP membership. This is not the case with Oneworld. I am also surprised by the lack of First Class lounges in Star-Alliance. United doesn't have one, All Nippon Airways and Singapore Airlines have but you can't use unless you fly First Class. Compared that to Oneworld's lounges in Hong Kong, Sydney, London Heathrow and various places in the U.S., Star-Alliance lounges seem to be slightly lower in standards.