Does TP-Link just make buggy stuff, or are we just unlucky? I used to have a TP-Link WiFi 6E router, that I used as an access point and a switch (the "routing" was disabled since I use another router).

For whatever reason, that device would drop packets if they were VLAN-tagged. Other packets were fine, but anything to do with VLAN just didn't work. Took me a while to figure out that was the issue and it wasn't with the machine I was trying to configure.

I sold that thing on eBay and replaced it with a "real" access point (and a PoE switch).