i've noticed they removed a bit of content in starbound, but they added some stuff in that actually made it more fun. the morphball tech is really fun, the story's actually kind of nice along with the missions you get, it's all really good imo
they'll add more content in the future. nothing's going to disappear FOREVER unless they say it is.
i also still enjoy running around the planets and exploring, and building and whatnot. finding weapons and trying out the special abilities is cool to see.
really, that's my thoughts. i'm not the people that don't like it, and if it's because they miss the content, i'm not really sure what to say. i can't fix that, i'm not the devs. maybe someone will make a mod and readd everything in.