Not the WiFi access point fix, but I have now identified the additional reason, why I had to additionally reboot the separate router on so far 3 occasions.
22.03.2 seems to have a randomly crashing DHCP service.
When it happens, previously connected devices (that already got an IP) continue working, while newly connected devices though establishing a Wifi connection refuse to transfer anything (as they dont seem to get an IP address). So if not checking thourpughly, it may look like only a single device is affected.
Today it was concidence: I first noticed that other issue on my PC via LAN cable.
On previous occasions it sinply went unnoticed that LAN equipment or other reconnecting devices would suffer as well.
others seem to have noticed the DHCP issue as well: