IMO the first two movies and scores cannot be overrated; they are masterpieces to me.
ROTJ isn’t overrated - I think the general consensus is that’s it’s the weakest of the OT by a decent amount. The movie is fine (aside from Ewoks, Solo’s character development, and Special Edition changes) and the score is good (I wish the recording was better though - it seems to have a “thinner” sound than the first two).
The prequel movies are trash and are only good for watching fun-ish lightsaber fights and enjoying those sweet, sweet memes from r/prequelmemes. TPM’s score is underrated IMO - I think it’s the best of the PT by far and is close behind ROTJ.
The new movies are tricky to talk about. TFA is an ok movie, and the score is very much above average. I still don’t know how to feel about TLJ as movie. It’s the only Star Wars movie in the main series I’ve only seen once (opening night in a theatre full of sweaty nerds), so I guess that says something. I’ve listened to the OST a handful of times and I like it as much as I like TFA. But they are nowhere near as good as the OT and I don’t think anything thinks they are. So they seem to be rated correctly.
OT movies: rated correctly
OT music: rated correctly
PT movies: overrated due to fire memes on the internet
PT music: overrated besides TPM
ST movies: who knows
ST music: rated correctly