Quick draft (to expand upon later):
1: Ideas purely based on reality (no hypotheticals, no fantasy worlds, no counterfactual thinking, no normative statements, no desires). Hypotheticals, fantasy worlds, counterfactual thinking, normative statements and desires (what I call "Irrealis") are considered lies, and the possible functions of pragmatic use, expressing desires or providing entertainment through fiction are ignored. This view is morally nihilistic, as morality is considered a lie, as well as desires in general. The future may or may not be deemed as "real", depending on the exact view.
2: Irrealis is acknowledged for its possible uses (mentioned above) but the existence of such counterfactual or fantasy scenarios is denied.
3: The existence of counterfactual or fantasy scenarios is considered real, and this is a philosophy that actually exists and is called modal realism.
4: Only ideas that may apply to our real world are considered, even if unpopular, or even if an individual may be the only person using that idea (as long as that idea applies to our real world and not just to fantasy worlds). For instance, (in some worldviews) "race" is a social construct, and so, for example, the way the US government has categorized race into "black", "white", "asian" and "native american" is totally arbitrary and based on historical and cultural contingencies. That means, it could had been different. In this #4 category, only ideas that apply to our real world are considered, for example, it's possible to create a racial categorization that is the following: blight (includes people that are currently labelled "white" or "black", which are included in this category of "blight" without distinction), non-Japanese Asian, Japanese, native american. It's a perfectly coherent categorization, the reason it wasn't formulated that way is just because of historical and cultural contingencies (and the concept of "race" was formulated for no other reason than to justify the slavery of "non-white" people from "white" people, by the way, so for practical reasons it was extremely unlikely that a category such as "blight" would ever be conceptualized, even if it is philosophically coherent). In short, this category refers to the possibility of applying "unorthodox" categorizations to things that exist in the real world (as opposed to things that are fictional, hypothetical or non-existent). For example, "blight" people are covered by this category, since although the category itself is considered unorthodox, "blight" people exist, but blue-skinned humanoids that fire lasers from their eyes do not and so they are not covered by this category. Whether or not categorizations (whether common or unorthodox) are considered "Irrealis" may be up to interpretation.