Gigabit Speed Only on Speedtest.net

Hello there! As the title states, I only see Gigabit speeds on speedtest.net. Any other download or speed test tops out around 550mbps-600mbps. If I turn on a VPN through WireGuard, I get the full gigabit speeds on those same speedtests that only provided 500mbps just a minute before. It seems a lot like aggressive traffic shaping, though I'm thankful that my VPN, which shows up at 'other' in my bandwidth usage, appears to get the same priority as speedtest.net. Maybe because they can't identify the traffic, it bypasses the QoS rules? Does anyone else experience this? This wouldn't be a provisioning issue is it? I am in Ocala, FL.