I don't really see Cheetah changing identities as a problem. Characters changing identities is pretty common, Marvel does it all the time with but with their heroes instead of their villains ironically. Plenty of comic fans don't even know about Sebastian and Debbie and Pricilla is only well known from Superfriends. I think the Brave and the Bold cartoon used Pricilla more than the comics have this past decade. I honestly wouldn't be surprised if casual fans just assume Barbara is the Cheetah from the 40's, they are both blonde now.
Barbara has been the main Cheetah for 34 years. She's the one everyone thinks about when you mention Cheetah, casual fan or not. Even the Wonder Woman '77 comic used her and not Pricilla, (I know it was because Pricilla had died but it would have been more accurate for them to use Debbie if they wanted to stick with the time period). Barbara is the main-stay Cheetah and I don't see that changing anytime soon, especially after WW84.