Why are broadband speeds different on Windows 11 laptops compared to Android phones?

• I had an upgrade to my broadband to 900/100Mbps yesterday.

• 3 x Android Pixel phones (2x Pixel 6, 1x Pixel 8) all achieve ~900/100Mbps no problem.

• 3 x Windows 11 laptops (2 work laptops from different companies, 1 personal laptop) – all max out at ~320Mbps.

• I have tried the laptops on wired and wireless connections – all give the same result.

• The Ethernet is negotiating 1Gbps

• 6GHz WIFI band / 2402 Mbps Tx/Rx link rate

• Auto-tuning: Normal, RSS: Enabled

• All tests completed multiple times over Ookla, BT, Fast.com, and Cloudflare all with almost exactly the same results

• Ping is ~12ms with 0% packet loss

Any ideas?