The problem with these sorts of films is that they actually fall in the genre of disaster films (as do films like ID4, Jurassic Park, etc). The hook of disaster films is to see how ordinary people react to crazy things happening all around them. T1 was about watching Sarah Connor react. T2 was about watching young John Connor react. Those films worked because that was interesting. T3 was about watching John Connor's wife Kate Brewster react but I don't think the actress was able to carry it. T4 was a complete misstep and veered off into the far future which probably shouldn't happen as there was were no ordinary people left in the future. T5 was another misstep because none of the main cast were ordinary people reacting to crazy killer robots. T6 has a few new characters in the main cast, maybe they will be ordinary people reacting to killer robots but I don't know if they can carry the film.
I don't think the Terminator series should be shelved. I think the people in charge of the franchise simply don't understand the material and haven't for 2 films now.