Sorry, what? "Racism" is not a word with a clear definition over time. It didn't exist at all in popular usage until the past few decades.
I think what you're trying to say is that "racism" is supposed to connote direct discrimination, like support for segregation, slavery, stuff like that. And sure, lots of people use the word that way. Most of those people are the same people who want to argue that "racism is a solved problem", so it's easy to see why this definition is attractive to mostly-male, mostly-white, mostly-conservative people.
But it's not the way a lot of other people use the word, where it connotes broader injustice in society and not just individual opinions.
Basically: you're making a senseless semantic argument. Even if you win the dictionary war about what "racism" means, you're still not responding to the actual concerns being expressed.