Nope, people in the south, black and white fly the flag as a symbol of southern pride. Less than 1% of southerners owned slaves. The war was about states rights for 99% of people.
The "Proud Boys" are unrepentant racist asshats and did not back Biden. In fact they showed up in mass to the insurrection in support of a man needing to be jailed under Title 18 Chapter 115 Section 2385 of the US criminal code. That's real news. Look it up and confirm.