backoff when internet is unavailable and constant wireless traffic

i noticed on AP, that yeelights are never having idle on AP more than a seconds, while some other IOT devices could be idle for minute without problem.

That basically means lights are poluting wifi spectrum.
But i wonder what it is, as on IP firewall i don’t see traffic so often. I guess some wifi-layer issue in light.

Also tried to firewall access to internet (as i control lights over LAN control exclusively). But behavior is it tries to reach DNS each few seconds. And if i allow DNS, it tries to open TCP connection 5 times in 10 seconds and sends 8 UDP packets to same IP in 10 seconds … even after half a day with firewalled all but DNS.
Would be really nice, if it backs off and tries less often after some time.
Or eventually if i can disable Cloud access at all - e.g. could be enabled after power on and disabled with LAN command. Or also OK if it gets disabled from APP and stays disabled until factory reset.