Some whitehat guru might have used the term to convey that all blackhat SEOs are spammers. Calling blackhat SEO as spamdexing is like calling SEO as indexing. We generally use the term "spamdexing" for "indexing sites through spamming" but not for SEO. Moreover, the definition of the term calls SERPs as index which is awkward. Overall, I think that the term gives a negative impression of anyone who wants to know more about BHW. It's better to call BHW an internet marketing forum which mainly discusses whitehat and blackhat SEO.
