Client isolation doesn't help. That is just the access point not routing traffic between connected devices. The problem with WiFi is it is a radio signal. Everybody in range can receive 100% of all communication on that network. Just by being in range the attacker can do passive sniffing. No wiretap needed like with cabled networks.
WiFi is encryoed if it uses a password. So any public WiFi without a password can be sniffed by literally every device in range (no need to connect to the WiFi for sniffing). On public WiFi with a password, the radio signal is encrypted but everybody knows the encryption key. So everybody connected to the WiFi can still sniff the traffic of everybody else.
That encryption is only on the WiFi level, so encrypted radio signals, not on the actually traffic level (like TLS/HTTPS etc).
And the brain didn't even know it was naming itself.
The ancient Egyptians removed the brain before mummification because they considerd it to be basically useless. Later associations between motor control of muscles and the brain were discovered but it wasn't until the development of modern neuroscience that the brain was considered to be the seat of awareness, self and intelligence.