I think it adds some interesting new context, particularly around denial of origin and proclamation of homogeneity. E. G. It has always meant what I think it means. There is also the connotation of ignorance and post-hoc justification.
Maybe this fits under the umbrella of reformism, but is not synonymous.
"Sanewashing" is the charitable explanation: Someone convincing themselves that the slogan means something sane out of social pressure to conform and adopt a slogan they don't agree with. The less charitable explanation for what's going on is called "gaslighting": The people you're talking with know damn well the slogan means something insane, but they'll lie to you and act condescending and superior in order to convince you to ignore all of the evidence and accept a sane definition.
Maybe this fits under the umbrella of reformism, but is not synonymous.