I just tried - the monitor stays black - although my 2012 macbook pro knows I'm connected. LG manager says software is all up to date as well. Just seems my monitor doesn't power on when I connect my thunderbolt cable to my laptop. I'm open to ideas. Would love to get this to work in the interim

Its a mid 2012 macbook pro.
The macbook is essentially on when I connect to the monitor. I just plug my thunderbolt cable and it should technically turn the monitor on. What happens is, my macbook pro recognizes the monitor, but it doesn't display anything. Stays black. Whereas when I plug the 2019 in, it recognizes it, and the monitor displays.