If that bothers you, you'll love the nLab's page on the red herring principle :)
> The mathematical red herring principle is the principle that in mathematics, a “red herring” need not, in general, be either red or a herring.
> Frequently, in fact, it is conversely true that all herrings are red herrings. This often leads to mathematicians speaking of “non-red herrings,” and sometimes even to a redefinition of “herring” to include both the red and non-red versions.
Well, i usually use 'soy meat' example, which is obviously not meat. The case where adjective moves meaning outside of boundaries of original meaning, instead of just making it more precise, is kind of perverse. Perhaps people should use hyphen to make it one term in cases where the meaning is not result of composition (e.g. 'dwarf-planet' and 'soy-meat' vs. 'big planet' and 'pork meat').
> The mathematical red herring principle is the principle that in mathematics, a “red herring” need not, in general, be either red or a herring.
> Frequently, in fact, it is conversely true that all herrings are red herrings. This often leads to mathematicians speaking of “non-red herrings,” and sometimes even to a redefinition of “herring” to include both the red and non-red versions.
https://ncatlab.org/nlab/show/red+herring+principle