He also apparently is putting his company at legal risk by continuing to create a hostile work environment via his disparaging racial comments that are not only crass but also highly illegal in a workplace environment, as in company gets sued and settles for millions of dollars illegal.I would call him out publicly like he did to you., that was my original thought but i just noticed that he is retiring in 3 years. You're not going to get him to change. He does have valid points and sticking it to him now will just cause more problems instead of getting him to stop.
You can politely in the public email let him know to bring these to your attention privately as its a bit unnecessary to ping the entire group of people. Thank him for his feedback, let him know you'll make those changes and you'll slow down a bit. If he comes back, you'll look even more like a jackass/confrontational which will likely draw others attention. You end up acknowledging him but also putting him in his place. Be the bigger man, and if he makes mistakes, bring them to his attention privately. Show him how you'd like things to be done, over and over again even if he doesn't change. If you can't win by brute force, win through actions of kindness.
Typically, I call bullies out publicly and even confront them and put them in their place but he sounds less like a bully and more like a grumpy old man. Since you can't tell him off and avoid him, you'll need to learn how to live with him.