My understanding is it’s removed by using your iPhone. If you follow my instructions it will be removed. This is how it’s worked from years and perhaps since the launch of the Apple Card in 2019.
Apple Card terms and conditions require you to have a supported device, iPhone or Apple Watch, iPad or Vision.
”Required Device” means an iOS device with a version of iOS installed that supports use of Apple Card in your Apple Wallet, a visionOS device that has a version of visionOS that supports the use of Apple Card or an iPadOS device that has a version of iPadOS that supports the use of Apple Card. A Required Device must have internet access and a passcode enabled.”
https://www.goldmansachs.com/terms-and-conditions/Apple-Card-Customer-Agreement.pdf
While MacOS devices have limited support because they do not have an actual Wallet app.
There are other Apple Pay and Apple Card features that require an iOS device to remove such as AutoFill addresses for Apple Pay.
In fact I tested what I wrote several hours ago. When I removed the card using my iPhone, it was removed on my iMac within the hour.