Verizon offloaded their email accounts to AOL before dumping most of their non-yankee landline customers on Frontier. They then bought back the accounts by buying AOL. So yes, it is a still operating subsidiary of Verizon just like Yahoo.
So Frontier customers bought from Verizon can’t get a Frontier email address, but they keep a Verizon one that actually resolves to AOL.
I don’t know if new Frontier customers get email or not. They may get an account through Yahoo.