In a general sense that's reasonably true.
This case, however, it a state level case in California. I believe you are in Canada, correct? The Republic of California has their own idea of how consumers should be informed. Companies are forced to label some products in a way that reads something like, "This widget contains XYZ. XYZ is known to the State of California to cause cancer." They only have to do it in California, and unless there's a practical reason to include it nationally (printing costs, for example), it's only done in California.
I'm not convinced that if Taco Bell loses that it will affect their national advertising much less their international advertising. It might, but I wouldn't consider it a given.
However, if this were a case brought by the FTC, I have little doubt that they'd change the advertising in Canada as well (if they lost).
I've found some subtle differences in how things are labeled from State to State and country to country, but the basic principles seem to be the same.
"Ground beef" is what's called a "standardized food product". That standard applies in both Canada and the US. "Ground beef" is identical in Canada and the US, as are the modifiers "extra lean", "lean", "medium" and "Regular", each denoting a specific fat content. The definition also allows for the inclusion of seasoning.
Based on that, what is considered "seasoning" in the US as it applies to the "standardized food product" "ground beef" should equally apply to food products here in Canada. If it didn't it wouldn't really be standardized.
What Taco Bell has labeled "seasoning" in the taco filling is somewhat questionable as it contains additives not normally considered "seasoning" under the FDA CFR 21 Part 170
Food Additives
Anti-caking agents 172.480 like silica, dried yeasts 172.896 aren't seasonings, although they are Substances Generally Recognized as Safe. 181.2-182.8997
Likewise the addition of oats in such large quantities doesn't act as a seasoning because it changes the physical properties (texture) and is used to retain moisture.
Based on all of this the term "seasoned ground beef" is in fact wrong. The "seasonings" Taco Bell lists don't match those considered seasonings in the definition of "ground beef" (plus their quantities are well beyond reasonable), and instead match those of the "substitute standardized product" known as "taco filling"
These standards apply in Canada, so what's taco filling in the US is taco filling in Canada, and what's "seasoned ground beef" in the US is "seasoned ground beef" in Canada. Any change here in Canada would affect the definition in the US and any change in the US would affect the definition here in Canada.
I'm fairly confident if this case makes it to trial they will be required to stop calling it seasoned ground beef. Despite what people have been saying in this thread the FDA and USDA definitions are very specific for a reason. The label on the package "taco meat filling" is 100% correct. "seasoned ground beef" is completely and utterly wrong. I don't see them allowing Taco Bell to take liberties with this "standardized food product" definition in ads and on TV.