Show me the post where someone said that. Show me.
Show you what? Show you where PC Revisionists claimed it was all about slavery? Where they said the South's entire economy was based on slavery? Where they claimed that even the vast majority of White Southerners who even they have to admit did not own any slaves were nevertheless motivated by protecting slavery? Where they conjure up some vast abolitionist movement prior to 1863 out of thin air? Where they claim that there was no real grievance other than slavery? They do that all the time. They've been doing that since at least the 1980s.
Its all things Southern that have been demonized from the Confederate Battle Flag to Southern political leaders and soldiers to the culture itself. I'm old enough to remember when the Confederate battle flag was flown all the time and nobody thought the message anybody was trying to send was "we hate Black people". I remember when the #1 show on television for several years running had a big Confederate Battle Flag on its roof. Nobody even considered that controversial.
Then Leftists in Academia decided it was "racist". Nobody ever asked us. Nobody ever took a vote on the subject. It just magically became racist and evil and bad all of a sudden.....because they decided it was. The same goes for any and everything else Southern. You're getting defensive because I've pointed out a lot of the things you want to accuse the South of in the mid 19th century were equally true of the North.