In what way is the subpoena hilarious? All of those companies to my knowledge are players in the VR space with hardware.
Google has Daydream, and working on more
Bytedance has the Pico's
HTC has the Vive
Huawei has one as well, don't remember it right now
Nintendo has something similar to daydream but for the Switch
Panasonic has the MeganeX
Samsung has the Gear
Simula have their headset
They all sell some form of headset hardware.