Because the economic sectors of those states reliant on slavery didn't have sufficient political power to lead their states into rebellion. Every state that seceded had greater than 25% of its population as slaves. None of the four slave states that remained loyal to the United States had more than 20%, and the average of the four was more like 11% slave. Even the order in which the states seceded, with a couple of exceptions, almost directly reflects their percentage of slave population.
You said, “Because the economic sectors of those states reliant on slavery didn’t have sufficient political power to lead their states into rebellion. Every state that seceded had greater than 25% of its population as slaves. None of the four slave states that remained loyal to the United States had more than 20%, and the average of the four was more like 11% slave. Even the order in which the states seceded, with a couple of exceptions, almost directly reflects their percentage of slave population.”
My point was more that these states within the union were still allowed to even have slaves which proves that this war was not about freeing slaves and abolishing slavery.