You also need to remeraber that anime hasn't been around as long as beef.
The term "Japanimation" has been around since at least the 70s, perhaps even longer. That's a mere 10 years after Astroboy, which is considered by many to be the first real anime, which means that Japanese animation has been put into it's own group for 80% of the time it's been around. However, you're trying to make it sound like people have just recently started segregating something that has been seemlessly intergrated with American animation up until then. Although the word has recently been replaced with a more modern-sounding word, it still serveed the same purpose that you've been crusading against.
If anime had been around for a few hundred years and people just recently started to single it out, then I think you'd have a much stronger case.