Google (GTS) has done the same. GTS controls GlobalSign R4. GlobalSign R4 was a root cert which was created by GlobalSign and later sold to Google.
If a bad actor starts buying up CA's, then very quickly that CA would be distrusted by Root Cert Store Operators. No different than what happened with DigiNotr and Entrust.
If a bad actor starts buying up CA's, then very quickly that CA would be distrusted by Root Cert Store Operators. No different than what happened with DigiNotr and Entrust.