Unless the person believes that old white men literally are not allowed to hold any opinion whatsoever on matters of sexism and that's the most plausible and popular view, then it clearly is both false and a strawman argument, so interpretation doesn't have much to do with it.

There are of course times when modern conversation around this devolve to people saying white men should just shut up, their opinions don't matter, etc. But since there are more defensible, reasonable versions of this (e.g., white men should be more tentative in opinions about discrimination given their relative lack of direct experience of being discriminated against, there are contexts when offering such opinions are inappropriate, etc.), it clearly is a strawman.