Exactly. Simple speech is able to get across simple concepts such as those of quick decision, and immediate action of concrete simple matters - such as "don't hold the hammer up so high on the handle," or "chew with your mouth closed!"
But, it is certainly not something to express complex concepts such as why this or that political/social issue is important/dangerous/whatever.
Sure, complex concepts can sort of be expressed in basic language. This would require, for one, a much greater number of words, and two, a shitload of unneeded mental effort on the part of the individual so simplifying it. In reality, many concepts could only be expressed with simple words if they were used to contruct things of much greater linguistic complexity - metaphors, symbolic references, etc. In such a way, the common man is still not able to gain understanding of such without becoming more than common. It isn't about bringing philosophy down to the common level, to the base idiotic level of society. Society seems to think everything is about that - leveling everything to the pathetic level of "everyone," and rejecting anything that is immortally above them.
There is one prominent example in history of expertly contructed philosophic & social concepts expressed in simple language - mythology. Mythologies, nearly all mythologies, are laden in extremely highly charged metaphors. The creation of the mythologies was a monumental effort undertaken by hundreds of generations of ancient intellectuals - philosophers before the concept of "philosophy." In such they were so perfectly contructed that even turning them into things of complex [philosophic] language would ruin the concepts that were so amazingly expressed through symbolism, metaphorism, and layers and layers of such linguistics.
But the funny thing about mythology is that the common man could never fully grasp it's scope, but could still fully benefit from it. The philosophic social & political ideas were not taught by bluntly trying to explain that which can't be explained in such ways. They were taught by rather directly bringing the philosophy to their lives, but not in a way that made it a static norm for everyone - rather one that could never allow such an atrocity. Mythology was not about understanding the philosophy, it was rather about "living it." The common man was led, led firstly by the greater order, the ideal; and secondly by the greater men - as they were the creators and sustainers of this.
Only the philosophers, the leaders, the "great" individuals, are meant to really ever understand. In the modern day everyone "must" understand, therefore society and politics are run by idiotic and foolishly simple ideas - ones that a drooling manchild can easily grasp. Everything is lowered to a base retarded level - hedonism and materialism. Beyond this, if this system doesn't self-destruct, will be an even more disgusting and frightening prospect - ideas that are sustainable and stable - utopian ideas - the creation of a single human that populates the entire earth and lives for nothing but to live in the most base empty biological manner.