BGW210-700 IP Passthrough to Asus AC3100 Getting Less Than Half Speed of 1000Mb/s Fiber Connection

I’ve read just about every forum and thread at this point and it seems like there might not be a solution, but thought I’d try and get some feedback.

What I Have:

• AT&T BGW210-700 - verified 1000mb/s down

• Asus AC3100

What I Did:

• Reset both the BGW210 and AC3100 to factory default

• Set BGW210 IPv4 to 192.168.1.1

• Set BGW210 DHCPv4 to 192.168.1.2 - 192.168.1.253

• Enabled IP pass through to the AC3100.

• Disabled all firewall advanced options on BGW210

• Disabled packet filters on BGW210

• AC3100 LAN is 192.168.2.1

• Verified the IP on AC3100 is the same when checking “whats my IP” on google

• All firmware is up to date​

Issues:

• When connected to 2.4Ghz I can only get ~80Mb/s down on any device.

• When connected to 5Ghz I can only get ~480Mb/s down on any device.

I know that this router should be capable of getting the 1000Mb/s down that I’m getting from AT&T fiber. Any ideas on how I can get closer to that? I understand there will be some loss on WiFi but the 80mb/s and 480mb/s seems WAY too slow. Are there some additional configurations I’m missing?