The way to remember people is in museums, libraries, and history books. The way you honor people is through statues and monuments. Many confederate monuments were erected well after the civil war. If Robert E. Lee had a statue erected that wasn't demolished during the war then I'd agree that's a part of history. A bunch of white people wanting to erect a statue in his honor 100 years later doesn't deserve the same reverence. Removing them does nothing to erase people form history. Nobody is promoting the erasing of history, you just have white southerners who feel hurt that they can't honor the losing side.

Robert E. Lee himself said that there shouldn't be confederate monuments.