Raspberry Pi 4B & OpenWrt 22.03 - Onboard 2.4Ghz Wifi not functional (AP/Master mode)

I can get onboard wifi to work in 5Ghz without issue. Unfortunately no matter what channel I set or config change I make, I'm unable to get the onboard wifi to function in AP mode at 2.4Ghz (via Luci). Is anybody else experiencing this issue?

Luci says:
Cypress CYW43455 802.11bgnac
Device is not active

SSID: OpenWrt | Mode: Master
Wireless is not associated

logread errors:

Sat Sep 10 21:41:00 2022 daemon.notice netifd: radio0 (13776): command failed: No error information (-524)
Sat Sep 10 21:41:00 2022 daemon.notice netifd: radio0 (13776): command failed: I/O error (-5)
Sat Sep 10 21:41:01 2022 daemon.notice hostapd: Configuration file: /var/run/hostapd-phy1.conf (phy wlan1) --> new PHY
Sat Sep 10 21:41:01 2022 kern.info kernel: [ 4091.124163] br-lan: port 2(wlan1) entered blocking state
Sat Sep 10 21:41:01 2022 kern.info kernel: [ 4091.131214] br-lan: port 2(wlan1) entered disabled state
Sat Sep 10 21:41:01 2022 kern.info kernel: [ 4091.138297] device wlan1 entered promiscuous mode
Sat Sep 10 21:41:01 2022 daemon.err hostapd: Driver does not support configured HT capability [SHORT-GI-40]
Sat Sep 10 21:41:01 2022 daemon.notice hostapd: wlan1: interface state UNINITIALIZED->DISABLED
Sat Sep 10 21:41:01 2022 daemon.notice hostapd: wlan1: AP-DISABLED
Sat Sep 10 21:41:01 2022 daemon.err hostapd: wlan1: Unable to setup interface.
Sat Sep 10 21:41:01 2022 daemon.notice hostapd: nl80211: deinit ifname=wlan1 disabled_11b_rates=0
Sat Sep 10 21:41:01 2022 kern.info kernel: [ 4091.179749] device wlan1 left promiscuous mode
Sat Sep 10 21:41:01 2022 kern.info kernel: [ 4091.185916] br-lan: port 2(wlan1) entered disabled state
Sat Sep 10 21:41:01 2022 daemon.err hostapd: rmdir[ctrl_interface=/var/run/hostapd]: Permission denied
Sat Sep 10 21:41:01 2022 daemon.notice hostapd: wlan1: CTRL-EVENT-TERMINATING
Sat Sep 10 21:41:01 2022 daemon.err hostapd: hostapd_free_hapd_data: Interface wlan1 wasn't started
Sat Sep 10 21:41:01 2022 daemon.notice netifd: radio0 (13776): Command failed: ubus call hostapd config_add {"iface":"wlan1", "config":"/var/run/hostapd-phy1.conf"} (Invalid argument)
Sat Sep 10 21:41:01 2022 daemon.notice netifd: radio0 (13776): Usage: ubus [<options>] <command> [arguments...]
Sat Sep 10 21:41:01 2022 daemon.notice netifd: radio0 (13776): Options:
Sat Sep 10 21:41:01 2022 daemon.notice netifd: radio0 (13776):  -s <socket>:            Set the unix domain socket to connect to
Sat Sep 10 21:41:01 2022 daemon.notice netifd: radio0 (13776):  -t <timeout>:           Set the timeout (in seconds) for a command to complete
Sat Sep 10 21:41:01 2022 daemon.notice netifd: radio0 (13776):  -S:                     Use simplified output (for scripts)
Sat Sep 10 21:41:01 2022 daemon.notice netifd: radio0 (13776):  -v:                     More verbose output
Sat Sep 10 21:41:01 2022 daemon.notice netifd: radio0 (13776):  -m <type>:              (for monitor): include a specific message type
Sat Sep 10 21:41:01 2022 daemon.notice netifd: radio0 (13776):                  (can be used more than once)
Sat Sep 10 21:41:01 2022 daemon.notice netifd: radio0 (13776):  -M <r|t>                (for monitor): only capture received or transmitted traffic
Sat Sep 10 21:41:01 2022 daemon.notice netifd: radio0 (13776):
Sat Sep 10 21:41:01 2022 daemon.notice netifd: radio0 (13776): Commands:
Sat Sep 10 21:41:01 2022 daemon.notice netifd: radio0 (13776):  - list [<path>]                 List objects
Sat Sep 10 21:41:01 2022 daemon.notice netifd: radio0 (13776):  - call <path> <method> [<message>]      Call an object method
Sat Sep 10 21:41:01 2022 daemon.notice netifd: radio0 (13776):  - subscribe <path> [<path>...]  Subscribe to object(s) notifications
Sat Sep 10 21:41:01 2022 daemon.notice netifd: radio0 (13776):  - listen [<path>...]                    Listen for events
Sat Sep 10 21:41:01 2022 daemon.notice netifd: radio0 (13776):  - send <type> [<message>]               Send an event
Sat Sep 10 21:41:01 2022 daemon.notice netifd: radio0 (13776):  - wait_for <object> [<object>...]       Wait for multiple objects to appear on ubus
Sat Sep 10 21:41:01 2022 daemon.notice netifd: radio0 (13776):  - monitor                               Monitor ubus traffic
Sat Sep 10 21:41:01 2022 daemon.notice netifd: radio0 (13776):
Sat Sep 10 21:41:01 2022 daemon.notice netifd: radio0 (13776): Device setup failed: HOSTAPD_START_FAILED
Sat Sep 10 21:41:01 2022 daemon.notice netifd: Wireless device 'radio0' set retry=0
Sat Sep 10 21:41:01 2022 daemon.crit netifd: Wireless device 'radio0' setup failed, retry=0
Sat Sep 10 21:41:02 2022 daemon.notice netifd: Wireless device 'radio0' is now down

Set the mode to Legacy for 2.4Ghz. Then it will work.

Thanks, I'm able to get the adapter to (look like) it comes up but the SSID is not broadcasted or visible whatsoever. Changing channels, rebooting, doesn't help.

Did you read the log you posted?
You can probably get this working by selecting 20MHz mode.

Note: The built in wireless on any Rpi is based on low cost chipsets designed primarily for use in STA mode (ie for connecting a device to an existing AP, not for actually being an AP), and are therefore little use, if any use at all, in a router.