There's a bit of new research and new recordings but if you already know the Hill's story then this doesn't really add much.
There are a few strange omissions such as how some psychiatrists wrote the entire abduction off as one big hallucination due to the difficulties of being an interracial couple and how the hypnosis sessions were criticised for "prompting" Betty and Barney, despite that not always being the case -- especially where important detailed scenarios are described by the abductees.
As in most of these types of documentary series', the over-use of spooky alien eyes and repeated transitions of a ship flying over or an alien looking at the camera with some glitchy effects is prominent. There's also a lot of AI upscaling used for old photos of the couple -- these images would have been better with basic noise reduction tools as the upscaling creates artifacts that make the couple's faces look hilarious (think silly misshaped mouths and eyes)
The doco finishes off with a clip of a much-older Betty where she claims that they were the first couple to be abducted -- a bit of a silly thing to include if you want to push their credibility as it makes it seem like they were proud of the publicity the abduction caused.