Variety's Justin Change shared similar views, calling it "back-to-basics and confoundingly revisionist".
"The movie's willingness to veer crazily off-course feels less objectionable than the monotony and sense of self-parody that kick in long before the whimper of a finish.
"The Terminator franchise, by now, has become its own worst Skynet - a monument to self-regeneration that endlessly repackages the same old thrills in ever sleeker, sexier models, and that gladly screws with its own past to ensure its future survival."
The wrap headlined James Rocchi's review with: "Schwarzenegger's Swagger Can't Save This Redundant Tentpole."
"The least inspiring thing about Terminator Genisys is how it's a fifth film that doesn't improve or expand on the prior four so much as it's meant to clearly set up Part Six, Part Seven and possibly even more," wrote Rocchi.
"In 1984's The Terminator, machines came back from the future to wipe out humanity; with Terminator Genisys, a whole franchise comes back from the past to water down summer moviegoing."
Slashfilm was more positive, calling it "the best Terminator film since Terminator 2".
"It is a clever take on the idea of the reboot/sequel, which really takes advantage of the series' time travel premise to make things fresh again," wrote Peter Sciretta.
Terminator Genisys opens in New Zealand on July 1.
- nzherald.co.nz