The TFA-era materials, along with Bloodline, do suggest a great deal of dysfunction within the New Republic -- especially with the latter telling us this continued even after the Centrists seceded to form the First Order. By the same token, I wouldn't take an unwillingness -- even of Leia's "allies" -- to intervene directly in a military situation to suggest everyone is OK with the First Order taking over or that nobody wants to save the Republic. We still don't know how much of the Republic is left and what they're willing to do. As Nick points out, it's the neutral systems that are surrendering en masse. It really depends on what the Republic worlds, without the central NRDF and government apparatus, can do. It's entirely possible they're not in the best position to resist. I mean, the FO blew up Hosnian Prime for a reason.