Real ID only confirms one was lawfully present in the United States when the ID was issued, it is not intended to prove citizenship.
https://www.dhs.gov/archive/real-id-public-faqs
For example, DACA recipients, temporary protected status refugees, and citizens of states in free association with the USA (Micronesia/Marshall Islands/Palau) that are in the USA are all eligible for Real ID.
Correct. My understanding of the SAVE act is that it would require an enhanced RealID drivers license to act as sole proof of citizenship, which is a type of license only issued in 5 states (all bordering Canada) that can act as proof of citizenship when driving across the US-Canada border. Even people with a valid RealID would be required to bring an additional form of ID to prove citizenship, such as a birth certificate. The fact that this is confusing to people is, in and of itself, a huge red flag for the impact this will have on voter participation.