Same problem here, latest 11.6 and still happening after doing every possible step found online. Mojave/Catalina sleeps without any issues. I even tried to install 12.0 using OpenCore Legacy Patcher and the same problem occurs. Pre-Big Sur releases sleep properly. Seems Apple screwed up something for at least some older MacBooks, mine is mid-2014 pro with gt750m.
matthewmkb
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