Why is WiFi slow on kernel 6.17 but not 6.11?

My WiFi connection became noticeably slow recently on a KDE Neon system. To bisect the issue I’ve tried rolling back to kernel 6.11 and it works fine there but doesn’t work on the latest HWE (6.17.0-19-generic). I can see that the connection speed in the applet shows 54 mbps. Any idea what the issue might be? ChatGPT said it might be due to the interface country not being set correctly since the channel shows no HT - is that right? Here is my network info: iw reg get; iw dev wlp0s20f3 info; sudo lshw -C network global country US: DFS-FCC (902 - 904 @ 2), (N/A, 30), (N/A) (904 - 920 @ 16), (N/A

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