You're using the relatively recent redefinition of the term "racism", that claims that racism is
only systemic prejudice from a position of power (the so-called prejudice+power definition).
With this definition, yes, it is impossible to be racist to white males in US.
The problem is that this definition is not what the word actually means in colloquial English. So when most people talk about racism, they have that conventional definition in mind, not the stuff that social studies use these days.
And frankly, this attempt to rewrite the dictionary doesn't seem to have any reasonable justifications. We already had various terms and combinations of terms that describe the nuances fairly well - we had "racism" to mean "racial prejudice", and we had "systemic racism" to mean prejudice+power.
The only reason why I can see to change these around, to, effectively, replace "racism" with "racial prejudice", and "systemic racism" with just "racism", is because "racism" became a word with extremely heavy negative connotations. And some the same people who campaigned for it to become that - and rightly so, IMO - became uncomfortable with the fact that those negative connotations now also applied to some members of minority groups (e.g. the New Black Panthers). With the new definitions, this problem disappears - NBP is "prejudiced", but they're not "racist" anymore.
And this is very problematic, because the result of that is that bona fide hate speech - like, literal explicit calls for murdering people based on their race - is treated as more acceptable than e.g. pay disparity.