I don't see the point in redefining racism to always be systemic/institutional. Can you please clarify the benefit for me? (I say redefining, because I haven't found that definition in dictionaries, popular sources or government sources, nor heard it in person even in socialist circles.)

Power exists throughout society and I don't believe individuals can be divorced for the systems they form. So it seems to me that limiting the scope of the term 'racism' trivialises the important role that individual racial discrimination plays in forming and consolidating systemic racism. How large does a system have to be to create racism? It doesn't take many people to remove someone's housing opportunities, income, public safety and other basic essentials.