For Linux, avoid docks with DisplayLink in the description. It's a weird driver-based solution that doesn't work well IMHO.
Yeah, I tried a DisplayLink dock a handful of years ago. Ports for external monitors didn't work at all, ended up being an over-priced USB hub.
I ran into this problem with my work laptop and dock and yes the fix is super weird but once applied it worked flawlessly. I'd definitely avoid if possible but if the dock you love has it look into the documentation to install and see if you're comfortable running a few weird commands.
That dock uses a DisplayLink chip.
A DisplayLink chip is essentially a tiny GPU that handles the final outputting to the display. When the DisplayLink chip is in use the laptop's GPU still does 99% of the work, but the DisplayLink chip handles the final outputting to the display.
This has the major advantage of allowing it to work with a much wider selection of devices (almost anything with a USB port and a DisplsyLink driver available), however the additional complexity and drivers can lead to some finicky behavior and artifacting. Overall I suggest avoiding DisplayLink docks unless you actually need the benefits.
For the Framework Laptop most Thunderbolt 3/4 and USB4 docks should work, but not all.
USB4 supports two different methods for a dock to run multiple monitors. The computer can send multiple separate display signals to the dock or the computer can send a single (higher bandwidth) display signal that the dock can then split into multiple display signals.
From the end user's perspective those are identical as long as they work, however AMD USB4 controllers (like the ones in the FW16) only work with the latter method (single display signal that is split) whereas MacOS works better with the first method.
Most USB4/Thunderbolt 3/4 docks use the method that works with AMD, however some docks that are marketd towards Mac users will not work. The most common docks that won't work are Caldigit docks.
If you want a docking station that works with either the Framework or a MacBook then that may be a good reason to use a DisplayLink dock.
Thank you for the detailed post! I have a really old display link usb dock and an USB c lenovo dock for work that I may play with once I get my hands on the FW16.