NIC intermittently receiving many duplicate TCP ACKs?

I have been having intermittent spikes in response time with HTTP(S) traffic on WiFi that last varying amounts of time. (Or at the very least HTTP(S) traffic, I do not notice it with Spotify's audio for example.) This has only been happening since I moved from Debian 11 to Debian 12, though I cannot pinpoint when exactly it started after doing that. (I also set up a new router within this time frame, so maybe that could be related?) It also only seems to happen after my machine has been on for some time. I ran Wireshark while it was happening and noticed that my machine was receiving a lot of

Question by dryhen on Super User, licensed CC BY-SA. We show a short excerpt and link to the original thread as credit.