Here's the thing. You said "vegan luncheon meat is spam."
Is it in the same USDA classification? Yes. No one's arguing that.
As someone who is a scientist who studies processed food, I am telling you, specifically, in science, no one calls luncheon meat spam. If you want to be "specific" like you said, then you shouldn't either. They're not the same thing.
If you're saying "luncheon meat category" you're referring to the economic grouping of the USDA, which includes things from Armour Treet to Great Value to Swift Prem.
So your reasoning for calling a vegan luncheon meat spam is because random people "call the one in the tin spam?" Let's get King Oscar and Chicken of the Sea in there, then, too.
Also, calling something meat or spam? It's not one or the other, that's not how nutrition classification works. They're both. Spam is spam and a member of the luncheon meat category. But that's not what you said. You said luncheon meat is spam, which is not true unless you're okay with calling all tinned meat spam, which means you'd call prem, treet, and other luncheon meat spam, too. Which you said you don't.