My colleagues and I have had a lot of “fun” recently, with a switch to new USB-C based MacBook Pros (the 2019, Intel model).
We’ve all got various different configurations of monitors in our home offices, plus new HDMI/DisplayPort capable monitors at work.
I still have a first generation (non-HDCP) 23" Apple Cinema Display. (I like those extra 120 lines!)
Previously I was able to use a Mini-DisplayPort to DVI-D adapter, but that wasn’t compatible with any USB-C to MiniDisplayPort adapters that I could find. In the end, I’ve been successfully using a USB-C to Dual Link DVI Active Adapter [link: Amazon UK] from “Cable Creation”. Although the 23" is not Dual link, the important part of the specs is, I believe, the “Active”. Another simpler, cheaper adapter I tried was not compatible with my non-HDCP display.
Some other tidbits of info that we’ve learnt…
We’ve been successful with a CalDigit Thunderbolt 3 Mini Dock to use those multiple DisplayPort monitors.
If you’ve got multiple HDMI displays and are thinking you’ll find something with one plug to connect to the Mac beware of getting adapters that need “MST” (Multi-Stream Transport) support. This is what some (the cheaper ones…) require to provide two outputs from one USB-C input but (as of Big Sur) macOS doesn’t support it. Not producing two different display outputs is usually buried in the small print or in the reviews of disappointed customers.
You can only connect multiple displays, via one plug into a Mac, with the (more expensive) Thunderbolt 3-based devices (like the above-mentioned CalDigit TB-3. It looks like they have an 2 x HDMI-output model too, but none of us have tried that one.)