For context, LDAC is one of the few wireless audio codecs stamped Hi-Res by the Japan Audio Society and its encoder is open source since Android 8, so you can see just how long Windows is sleeping on this. I’m excited about the incoming next gen called LC3plus, my next pair is definitely gonna have that.
if you tested on android then I wouldn’t be surprised, android is notorious for having sketchy AAC settings https://www.soundguys.com/the-ultimate-guide-to-bluetooth-headphones-aac-20296/
FDK-AAC is considerably better, I dont think I did a bitrate mod on it but I may have? I think pipewire by default caps AAC at 320kbps and can hold it reliably, and at 256k both opus and FDKAAC are transparent to the vast majority of people even on high end audio setups.