You might be referring to this but on top of hardware decode some Bluetooth setups can send the actual AAC file to the headphones and decode it there.
Traditionally Bluetooth audio meant decoding and reencoding it into a crappier codec before transmission. So it's an efficiency and quality win.
I think some Google Pixel Bud Pro earphones do this for Opus but that is rarer (there's a few other codecs that have been done like this over the years by different manufacturers).
That's their point though. Basically no modern phone/laptop/tablet other than Apple offloads audio decoding (of any codec) to hardware. You can check this on Android phones by installing the Codec Info app.
I’m pretty sure no x86 chip has hardware decode/encode for audio. Together with dGPUs, they tend to have decoders for JPEG and decoders/encoders for H.264, H.265, AV1 and sometimes VP9.