@AwfulCitizen 

So you know this post does ride the line of violating our community guidelines.  However, I wanted to ensure you received a response.  When Apple updated its operating system from OSX to OS11.0 and up there were several big feature updates made.  These updates make it very difficult for manufacturers to generate drivers for the new OS systems.  This actually happens more often than you think when an OS shifts from one major update to another.  For example, Windows going from 10 to 11 or Windows 8.1 to 10.  They also bring in the subject of hardware limitations.  For example, your Archer T9UH v2 launched in 2018.  Big Sur didn't launch till 2020.  Your adapter and the chipset it was built around were already 2 years old at the time of Big Sur's launch.  While we acknowledge concerns with providing official drivers for Big Sur and Monterey it is also quite possible for your particular case that drivers can't be provided because the chipset would not support them.  That is something that a customer will always have to deal with when new technology or software advancements take place.  The hardware just isn't compatible.  

Speaking of Chipsets.  It's actually the chipset makers that provide the initial driver for any compatible OS.  Then the manufacturer of the adapter customizes the driver or adds it to their installer programs.  This is why even with our adapters the compatible OS varies greatly.  Some adapters can support Linux and some can't.  Even some are windows only.  It all depends on the chipset that is selected for a product.  

As to purchasing an Adapter in 2022 specifically because it what it says it supports, we do include the versions of supported OS systems in the product's description.  For example for the Archer T9UH, in the bold text description, we say "TP-Link AC1900 USB 3.0 WiFi Adapter for PC(Archer T9UH)- Dual Band Wireless Network Dongle for Desktop with 2.4GHz/5GHz High Gain Antennas, Supports Windows 11/10/8.1/8/7, Mac OS 10.9 - 10.14" This tells a prospective buyer what it does and doesn't work with.  

You are welcome to leave whatever review you feel is appropriate but TP-Link is not at fault here.  We clearly state what OS our adapters are compatible with, at the time they are purchased.  We provide updates when possible which are posted on our official website.  We do understand that major changes in OS systems like Big Sur do create concerns about continued compatibility and we do what we can to address those concerns in an official manner.  Right now we are still waiting for the chipset makers to provide us with Drivers for Big Sur and Monterey.  Until then there is no official support for either of these two operating systems.  Once drivers are available we will be sure to post them to the support pages of the products that are compatible with the updates.  

You can also try this workaround, however it does require you to disable a feature in your OS (SIP) and is not supported by TP-Link.  It would be use at your own risk/discretion.

https://community.tp-link.com/en/home/forum/topic/239134