Based on the available evidence, it seems likely that the Huawei-made Nexus 7 tablet is indeed dead. This rumor first surfaced back in June, when a reliable leaker claimed that Google had cancelled the device. Since then, there have been no further reports about the device, and Huawei has made no official announcement.
One possible reason for the cancellation could be the recent launch of the Huawei MediaPad M3. This 8.4-inch tablet bears a strong resemblance to the Nexus 7, and it's possible that Huawei decided to kill the Nexus 7 in favor of the MediaPad M3.
Another possibility is that Google simply decided to go in a different direction with its Nexus tablet line. The company has not released a new Nexus tablet since the Nexus 9 in 2014, and it seems unlikely that it will do so in the near future. Instead, Google seems to be focusing on its Chromebook Pixel line of laptops.