This didn't use to be a problem. Famously people moved out of r/marijuana to r/trees because they had issues with the mod.

This was subreddit splitting/budding. Which has stopped because of automation.

Thats the tradeoff. Automation allows you to moderate and stop the hate speech.

It also means you can stop people from using the name of the new sub, so discovery is stalled.

So even your solution won't stop it, because we can't survive without automod.

Enjoy!