The whole 'no T3' thing is bull****.
It doesn't carry directly on from T3, but his wife's still Kate (she's a doctor now instead of a vet), Judgment Day still happened "14 years ago" as of 2018 - which about ties in with T3...
And I'm betting there's plenty of other bull****, because - guess what - the studio doesn't give a ****!
All they care about is marketability. So if they can back-reference T3 to keep the people who liked that piece of **** happy and increase the grosses, reviews and overall word-of-mouth then they'll do it.
About the only redeeming thing I can currently find with this movie is that Christian Bale has read the script and signed on to star. And he's generally pretty good at picking movies that actually have some artistic merit. Of course, McG could pretty easily rape that in the face with his 'vision'.