He wouldn't have to enthusiastically accept the saber in order to justify the anticipation following a two-year wait for the conclusion of that scene. If you're going to present the first Star Wars film in over a decade (TFA), and end it on a scene of Rey handing Luke a lightsaber he hasn't seen since Bespin (and belonged to his father), then I don't think it's unreasonable for fans to find the resolution to the scene (in TLJ) to be disjointed. If that was the planned outcome from both Johnson AND Abrams, then it amounted to nothing more than a "Ha! Gotcha!" That's a letdown.
Again, I don't object to Luke not accepting the saber; but some exposition regarding the fact that this saber has found its way back to him after so many years would have been nice. Instead, the famed saber ends up being nothing more than a red herring. In Force Awakens: Maz had it tucked away and indicated that it'd be a long story to explain her possession of it (building curiosity); the saber calls to Rey in what seemed to be a pivotal scene (more curious now); and the movie ends on it being presented to Luke (here we go!). All that build-up, just to have Luke toss it almost immediately. Then why take time to build up to that at all? Couldn't Rey have gone to Luke without the lightsaber as a prop to end the movie on? That's why it comes across as disjointed to me (and at least a few others). The brevity of Luke's response also seems like a cheap way to "shock" viewers.
The rest of the Rey-Luke story was really enjoyable for me. But, the saber scene remains frustrating. Congrats on recognizing that there would be no payoff to the build-up. I'm one of those who got suckered into believing that TFA was building to something more substantial in those moments when Rey and Luke first interact with one another. He wasn't connected with the Force, so he couldn't have seen the saber (or Rey) coming. Yet he was still distinterested in both coming across the galaxy to call upon him. I don't get it.