No WiFi networks detected - Manjaro - 2010 MacBook Pro

I’m on a 2009 mbp with identical wifi hardware working fine:

  Device-2: Broadcom BCM4322 802.11a/b/g/n Wireless LAN
  driver: b43-pci-bridge
  IF-ID-1: wlan0 state: up mac: <filter>

The problem is your:

wlan0 state: down

Might be a kernel issue, I’m on 5.10 LTS, check this post: MacBook Pro won't detect or connect to WIFI (BCM4322) - #3 by nulinuxbee