There is a lot of apparent miscommunication going on here. Network Discovery is a setting on Microsoft Windows. As far as I know Mac does not have that setting.
You seem hung up, or fixated, on what some other person posted 3 years ago about having trouble directly connecting their Mac to a My Cloud. That person didn’t provide any additional information on what troubleshooting steps they tried with their direct connection when they made that post. The person admits in their first post of that discussion they had problems with the My Cloud before trying the direct connection.
As repeatedly indicated you can directly connect a My Cloud to a computer. I do not have a Mac but the general process should be similar as it is with Windows. Do a 4 second pin reset on the My Cloud. Connect the My Cloud to the Mac by Ethernet cable/adapter, wait for the My Cloud to boot up, then try to access the My Cloud. You may need to disable the WiFi adapter on the Mac when using a direct Ethernet connection to the My Cloud. As a reminder, even WD Support (per the link I previously provided) indicates you can directly connect to a Mac.
There are other posts showing that direct connection to a Mac from a My Cloud device works.
