Air-gapped systems leak data via SATA cable WiFi antennas
bleepingcomputer.com
bleepingcomputer.com
... to a receiver that can be as far as 120 cm (on a specific DELL system, more like 30 cm for other PC's tested), after you infected[0] the system.
Trasmission can be as fast as 1 bit per second [1].
All in all I believe that people involved in keeping air-gapped computers secure will sleep well nonetheless tonight.
[0] not particualr easy for an air-gapped computer, but possible in theory
[1] possibly good enough to transmit a password, not so much for other data