I have the same issue as you "Slow download wifi speed on C7000v2". I initially have the Netgear c3700v2 modem router combo (Handles up to 300Mbps each on the 2.4 and 5G bands). Since I have switched to the "600 Mbps" plan with Comcast Xfinity, I want to upgrade my Modem and router.
That's when the problem started. First, I choose the Netgear C7000V2 modem/router (supposed to go up to 800 Mbps). When I tested on my phone. I only get up to around 250 Mbps sometime below 200 Mbps. I have trouble shoot this issue for 3 days after the purchase. I finally have to call up Xfinity Tech support to come to my house. Here is what they found: Signal coming out from the wall inside my house is 1200 Mbps. Hardwired to the C7000v2 is 700 Mbps. But Wifi is only around 270 Mbps. The Xfinity tech support does not know what causes this problem. The next day I called up the Netgear tech support. They asked me to change the channel and other configurations. But the issue still exists. I have been working with both the Xfinity and Netgear tech supports for a month. The issue is still unresolved. The Netgear tech support also had find out that there are 2 issues on my modem. 1. Under the event log - there is a T3 time out error. 2. On the upstream channel - the powers on each channel are little too high. They asked me first had to ask Xfinity to fix those problems first before the Netgear tech support can go further with the trouble shooting. The Xfinity tech support had already been out to my house 3 times (Today, Xfinity will send a Senior tech support to my house to look at the problem once again). I had also worked with the Netgear support every single day. Nobody knows how to resolve this problem yet. On my own trouble shooting, I purchased another C7000v2 to see whether it is a hardware issue. Same problem!! I then purchased another Netgear different model Ax2700 CAX30 (Docsis 3.1 up to 2.7 Gbps wifi speed). Guess what!! My download wifi speed went up to between 600 Mbps to 650 Mbps (sometime even to 700 Mbps). I assume there may be some kind of design issues with the C7000V2 since there are so many people have the same problem with slow WIFI speed on the C7000v2. I hope this message will help other Netgear communities on trouble shooting this issue.
