So far, you have not provided one iota of proof about the change that supposedly took place in the 1860s. You have shown that a President did overstep his authority when there probably was no need for such a deed. He could have gone for an amendment right then and there and it probably would have passed since the Southern States were not part of the Union. His bad deed offers no evidence of anything other than he overstepped his bounds. Congress pasing amendments when you say they changed the power and amendments were not needed belies your argument. And, as I stated earlier, there have been a few amendments since them. According to you, none were needed or necessary to affect change.
Sorry, but I don't see any validity to your argument. If what you say had been true, our government has been a tyrannical government and not a constitutional republic for many decades. While I believe our government is somewhat tyrannical today, I don't think the evidence shows that it was over the last 45 years of the 19th Century.
Unless you can show some evidence of this change at the time of the change, it will be my judgment that you are making up this theory and doing so out of thin air. If you think you can do so, please prove me wrong.