I admit that I've only seen parts of that film, but the reunion scene between Sarah and "Carl" is powerfully acted.
I suspect that a lot of people could not get past the initial premise, which admittedly read like James Cameron brandishing an upraised middle finger to the fandom.
That said, the preceding film (Genisys) was far too in love with its own presumed cleverness, even as parts of it read like fanfic. I do give them points for the briefly seen T-5000 (basically a mobile Skynet backup) and finding a T-1000 actor who looked legitimately creepier than Robert Patrick (Lee Byung-hun).