You can't be an expert on everything. Everyone is a lay-person in something. I used to scoff at warning labels myself until I realized that some people grow up without the benefit of parents or education. Those things that we think are obvious are, very often, not. We learned them from someone who cared about us.
Sure, but our effort should be put into making an education and learning accessible to those people, instead of normalizing stupidity by restricting everyone else's language.
Language by necessity must be restricted for it to have meaning. If a word can mean anything, it has exactly no meaning. By creating your own definition of the word you now must define it clearly otherwise you will spend all day arguing about "No True Scotsman".
What biologists have done in this case is removed the definition of "Lower Animals" from their context because there was no agreed upon definition of "Lower Animal." The term was too vague and could not be defined properly and was useless for scientific communication. There was no way to taxonomically define a "Lower Animal" except in a biblical sense. Even then, few can agree what it actually means.
