You said yourself, to random thoughts, that grammatical rules are all about consistent ability to effectively and accurately communicate. Changing conventions for a specific effect is one thing, but you can't really change them just because you don't like them, even though nobody else has adopted your change, and expect to be considered right.

In fact, there is an example right here in your very own writing where you left out the apostrophe and the context does not solve the meaning. You say, "despite most peoples ignorance of the cause." Do you mean ignorance that belongs to people, or ignorance that belongs to peoples? Because those are different words with different meanings, the latter being a plural form referring to multiple groups of distinct people. Unless we know about your "unless the noun ends in s" qualifier, which because you are using a set of rules that are not commonly accepted we would have no reason to, there is no way to pick out your exact meaning.

That is the trouble with using a rule set that is different from the one everyone else is using. It's like using a different form of chess notation that you've invented. It doesn't matter if you use it consistently or if it makes sense; all the other chess players are going to tell you it's wrong. And they're going to be right.

I do have some sympathy for your stance, because of the "it's vs its" convention. However, what you are arguing is that the apostrophe is not needed because context makes the meaning clear. But the exact same is true when you do use the apostrophe. Context makes it clear whether "everyone's" means "everyone is" or "belonging to everyone".

Given that context makes it clear in either case, what is the point of using a non-standard, non-accepted, this-is-my-personal-rule version when using it in the accepted way is just as understandable (and one could argue much more understandable because it follows the rules that people expect when they read something and does not lead to conversations like this)?

The only answer is that you have an idea you like and you're stubborn about it. Which, okay. No one can stop you. But you can't expect to be considered right about it, because grammatical conventions say that you are not, and that's what grammar is all about — it is a set of conventions that allow people to communicate accurately, and if you step outside of those conventions you are, by definition, no longer being grammatical.