Here's a definition from the ADL for systemic racism.
"A combination of systems, institutions and factors that advantage white people and for people of color, cause widespread harm and disadvantages in access and opportunity. One person or even one group of people did not create systemic racism, rather it: (1) is grounded in the history of our laws and institutions which were created on a foundation of white supremacy;* (2) exists in the institutions and policies that advantage white people and disadvantage people of color; and (3) takes places in interpersonal communication and behavior (e.g., slurs, bullying, offensive language) that maintains and supports systemic inequities and systemic racism." [1]
So if you support one of the "systems, institutions and factors", you are by this definition, racist. I just said most white people probably are, by this definition.