Probably because it’s a loaded argument and they are wise enough not to feed into the Left’s moral condemnation of America. Some slow wits think that the likes of Washington, Jefferson, Jackson will escape the fate being meted out their Confederate heirs.
“and they are wise enough not to feed into”
So the plan is to continue not responding and hoping it will just go away. Basically, respond with apathy.
This has been the plan over the last four decades of them calling the Founders racist. What exactly recommends this plan to you now as a good plan for the next four decades going forward?