think Paramount/Fox were expecting DF to be the 'Fast 5' of the franchise

they tried TG being the 'Fast 4' style successful relaunch ..but it didn't work..

So they try again (basically Genisys 2.0) but even more so (Arnie again but with Linda/Furlong & Cameron returning) like the 'Fast 5' of terminator

The idea being it does even better than TGs 440m worldwide so they'd then follow up with Fast6 of Terminator (probably bringing back the T1000/RPatrick and MBiehn as old Reese, and Cameron even more involved in script/producing) which would make even more, then further sequels becoming as huge as F789 etc (funnily enough the plane scene in DF felt quite similar to Fast 6 endless runway scene)

But instead DF has become like the 'Tokyo Drift' of the franchise! (actually maybe that was T4..with T3 as the 2F2F)