I think a ST could have been but it needed to feel more organic and also feel like the OT actually had an impact. When we're re-introduced to our heroes from the OT, Luke is a failed Jedi hermit, Han & Leia have split and Han & Chewbacca are back to smuggling, and Leia is once again leading a rebellion. At the end of RotJ the Empire was defeated, aside from whatever remnants remained, yet somehow in a relatively short period of time a new First Order has risen and taken control and the rebel alliance has either dissolved and/or shrunken down to nothing.
Every single OT hero either stayed the same or regressed. Their character growth was for nothing. We also got a new Death Star, a new Darth Vader, and Emperor Palpatine is risen from the grave. There's still a lot to like from the ST but boy does it feel like they didn't try their damnedest to make it what it could have been. Just watch the behind the scenes series with Dave Filoni and Jon Favreau. Those are two passionate and intelligent people that made a great TV series based on the existing SW universe. I'm sure those two could have done a much better job with the ST.
It would also help to have a Kevin Feige to keep everyone in check and make sure everything jives well between movies. That should have been Kathleen Kennedy but clearly she has been found wanting.