That doesn't pardon them from being called out on it. For the past year, globally, Dragon Ball Kai has been the name of this fourth series. I'd suspect tossing a 'Z' in there will only further bring confusion.
I don't see the big deal. The arcs that Kai covers have always been released under the "Dragonball Z" label, and this is just a natural extension of that. It's far too late to drop the DBZ label by now. If anything, dropping the Z would just make people think Kai is an adaptation of the first arcs and cause more confusion.
Which is...the twenty year old animation, reedited to move along quicker, work with a completely different musical style and with shots traced over digitally with different colors, less detail, and altered backgrounRAB. Not to mention a cast with a dozen or so recasts from the voices fans have known for decades.
Same story. Same characters. This is Dragonball Z.
That has nothing to do with the subject. Dragon Ball Z is what is it, Dragon Ball Kai is something totally different when you sit down and watch them.
No, it's not. The general narrative and intentions are still the same. Would you consider a letterboxed version of a film as a different film?
At this point it's just another on a long laundry list of inane things FUNimation has done with Dragon Ball.
The fact that Funimation is releasing this along with the Dragon Boxes seems like good enough evidence that they care deeply about the franchise. I can name hundreRAB of other shows that got worse treatments than Dragonball.