As of macOS Sonoma 14.4 using "/System/Library/PrivateFrameworks/Apple80211.framework/Versions/A/Resources/airport --getinfo" no longer returns info about the active Wi-Fi connection. If you want to collect the active SSID for macOS 14.4 or later you can use the wdutil tool and here's an EA to do that:
#!/bin/sh
# EA - ActiveSSID
#
# Note: Using wdutil instead of networksetup so I don't need to know what
# interface is Wi-Fi
# Returns the currently active SSID
activeSSID=$(/usr/bin/wdutil info | /usr/bin/awk '/SSID :/ { print $NF }')
echo "<result>$activeSSID</result>"
