Speciesism and Racism

When a non-vegan expresses their value of Humanity, it is a very common move to see a vegan say something along the lines of:
"If you are Speciesist then you justify Racism(Or sexism or whathaveyou)"
This article's purpose is to break down what that can mean.
Some Basics
Let's look at some things that statement might mean.
"If you hold an attitude that humans have a right to life that other animals may not have, then it is impossible to not hold a racist attitude."
That, on the face of it, seems immediately false. We can easily find people with attitudes that grant right to life for humans and not animals, and who are also not racist. I'm one of those people. If it was *impossible*, I and others simply wouldn't exist. Someone may try and defend this assertion by claiming that all these people really are racist and hiding it/don't know it. There's no where to go from there as it's inherently an unfalsifiable claim, you may as well claim you know the existence of the undetectable unicorn people. I simply will not take the claim serious.
"The process that allows you to come to a Speciesist value is the same process that allows you to come to a Racist value."
Now, this statement is actually ambiguous, and it comes from the word "you". "You" in this sentence can mean two things: It's pointing directly at *me* as a person, or, it's referencing "people in general" such as "It allows one to come to..." This is important to note because it's going to determine how we respond.
Metaethically, I defend subjectivism. Which, if you're unaware of what this means, is that the truth of moral statements are statements about individual subjects. So "You should not murder", to me, roughly translate to "I am the sort of person with a negative disposition towards murder and do not want it to occur."
Now, approaching the statement from a "people in general" perspective:
"The process that allows people in general to come to a Speciesist value is the same process that allows people in general to come to a Racist value."
And this would be true, subjectivism does not stop anyone from having any value. So long as it accurately describes that person, the value is true. However, let us realize this does nothing for a vegan advocate, because the statement:
"The process that allows people in general to come to a Sentient value is the same process that allows people in general to come to a Racist value."
Is equally true. Subjectivism allows for vegan positions and racist positions, Jainists and Antinatalists, Neo-Nazi's and everything inbetween. Subjectivism is a description of how ethics works, and it's non-discriminatory towards values. However, if we look at the statement the other way:
"The process that allows you (Shadow) to come to a Speciesist value is the same process that allows you (Shadow) to come to a Racist value."
Then this is false. The process of subjectivism, when applied specifically to me, only allows me to say values that are true of me. I'm unable to just say I have a racist value because I hold an anti-racist attitude. If I said I was racist, I would just be lying. But if I said I was speciesist, I wouldn't be lying.
So in examining the above statement, we get the following results:
1) It's talking about people in general and the statement is true of both me and the vegan, thus being trivial.
2) It's talking about a specific person and the statement can just be false.
The Logical Approach
Maybe what someone is saying when they say: "If you are Speciesist then you justify Racism(Or sexism or whathaveyou)"
Is that "Speciesism logically leads to Racism" and that "Sentientism does not logically lead to Racism"
Someone might try and argue it like this:
Species is a collection of physical traits.
Racism is a collection of physical traits.
Therefore, Speciesism implies Racism.
+
Sentientism is a mental trait.
Racism is a physical trait.
Therefore, Sentientism does not imply Racism.
Now, my quick reply to this is: This is a logical error. It's simply invalid reasoning.
The Error
Update: See the Article Don't Use Superset Reasoning.
=== Some other meaning ===
Perhaps when someone says "If you are Speciesist then you justify Racism(Or sexism or whathaveyou)" they mean something beyond what I have covered. All I can say is: I have no idea what you mean then. If you can offer some alternative explanation, please feel free to do so, but at the moment, any explored angle seems to just prove the statement incorrect, invalid or trivial.