"My question is what else would you call it?"
I would call it a Kioti - that is its name, after all.
Instead of generic or knock-off, I would have used the words competitive brand - this is what it is, after all.
Paint alone does not a knock-off make - it's been discussed before, but Kubota paint is only a shade or two different from Allis-Chalmers or some Agco-Allis. Also as mentioned before, Kubota did not invent the tractor or the compact tractor, nor did they re-invent the compact, but rather refined a proven design. I don't know who came up with the first tractor, but we can try to trace the origins back to the old steam traction engines and then kerosene engined-tractors, etc. etc. up through the 40s, 50s, 60s. So I guess, in that sense, probably every tractor on the market is a knock-off - after all, John Deere got their start building plows (I think) - they got in the tractor market after someone else had already building tractors.
...so we could just call tractors by their proper names...wouldn't that be a novel idea.