"If we had not fought the American Revolution, we'd still be under British rule. " This is a logical fallacy, ahistorical thinking. We did fight a revolution, and we are no longer under British rule. Those two parts are historical.
There is no basis to claim "we'd still be under British rule" since that is not what happened to USA.
But there is history of countries under British rule who gained independence without fighting a revolution. For example, Canada. And dozens of others.
So a historically valid statement would be, "We would have gained independence without fighting a revolution." Nothing in that statement conflicts with history.
Now you try: "If we did not fight the Civil War, USA would still have slavery." This too is ahistorical.
We did fight a civil war, and we did end private property slavery.
In the era we fought a civil war, 19 other countries ended slavery peacefully. So a historically valid statement would be "USA could have eliminated slavery without a civil war." Nothing in that statement conflicts with history.
It is important to speak accurately if you want what you say to matter.
Wars and revolutions for change only make matters worse. The USA had a good thing going until the bankers hijacked the peaceful independence movement by means of a constitutional convention. The enemy of peace in the USA, Alexander Hamilton, led the successful effort to create a corporation with banking at its core and a standing military, and call it the federal government.
His activities sound so contemporary:
We would be much better off if we had no wars and revolutions. That is a historically valid statement. Any claims to the contrary cannot be substantiated by history. I cannot celebrate war and oppression, but when the bankers control the textbooks, just about everyone else does.