Yeah, I've heard that and I see where she was trying to go with it but the other problem here is that we have no evidence that Snape wanted to protect Muggleborns except for Lily and by extension Harry. (I like to think eventually Dumbledore had a good influence on him but that's as far into Sevvyland as I'll go.)

Also comparing him to a real resistance fighter who lost her life seems... tacky, at best. At least in this context.