Some (older) devices not getting IP through WiFi

Installing and Using OpenWrt Network and Wireless Configuration
11

I decided that starting from scratch with Access Point configuration I of reasonable effort and AP seems to be the major source of problems here.

After I restored the AP to defaults its configuration looked like this:

root@OpenWrt:~# cat /etc/config/network

config interface 'loopback'
	option device 'lo'
	option proto 'static'
	option ipaddr '127.0.0.1'
	option netmask '255.0.0.0'

config globals 'globals'
	option ula_prefix 'fd87:xxxx:xxxx::/48'

config device
	option name 'br-lan'
	option type 'bridge'
	list ports 'eth0'

config device
	option name 'eth0'
	option macaddr '58:xxx:00'

config interface 'lan'
	option device 'br-lan'
	option proto 'static'
	option ipaddr '192.168.1.1'
	option netmask '255.255.255.0'
	option ip6assign '60'

root@OpenWrt:~# cat /etc/config/wireless

config wifi-device 'radio0'
	option type 'mac80211'
	option path 'pci0000:00/0000:00:00.0'
	option channel '36'
	option band '5g'
	option htmode 'VHT80'
	option disabled '1'

config wifi-iface 'default_radio0'
	option device 'radio0'
	option network 'lan'
	option mode 'ap'
	option ssid 'OpenWrt'
	option encryption 'none'

config wifi-device 'radio1'
	option type 'mac80211'
	option path 'platform/ahb/18100000.wmac'
	option channel '1'
	option band '2g'
	option htmode 'HT20'
	option disabled '1'

config wifi-iface 'default_radio1'
	option device 'radio1'
	option network 'lan'
	option mode 'ap'
	option ssid 'OpenWrt'
	option encryption 'none'

Then I have created a single WiFi network (and some interface to manage the AP) following advice from this topic. Now the configuration looks like that and none of the devices connects to the WiFi:

root@OpenWrt:~# cat /etc/config/network

config interface 'loopback'
	option device 'lo'
	option proto 'static'
	option ipaddr '127.0.0.1'
	option netmask '255.0.0.0'

config globals 'globals'
	option ula_prefix 'fd87:xxxx:xxxx::/48'

config device
	option name 'eth0'
	option macaddr '58:xxx:00'

config interface 'secured'
	option proto 'static'
	option ipaddr '172.16.16.2'
	option netmask '255.255.255.192'
	option gateway '172.16.16.1'
	option device 'eth0.16'

config interface 'iot'
	option proto 'none'
	option device 'eth0.32'

config interface 'home'
	option proto 'none'
	option device 'eth0.64'
	option type 'bridge'

config interface 'guest'
	option proto 'none'
	option device 'eth0.128'

root@OpenWrt:~# cat /etc/config/wireless

config wifi-device 'radio0'
	option type 'mac80211'
	option path 'pci0000:00/0000:00:00.0'
	option channel '36'
	option band '5g'
	option htmode 'VHT80'
	option disabled '1'

config wifi-device 'radio1'
	option type 'mac80211'
	option path 'platform/ahb/18100000.wmac'
	option band '2g'
	option htmode 'HT40'
	option channel '6'
	option country 'xx'
	option cell_density '1'

config wifi-iface 'wifinet0'
	option device 'radio1'
	option mode 'ap'
	option ssid 'Sxxx_Home'
	option encryption 'psk2'
	option key 'xxx'
	option network 'home'

So what am I doing wrong here?