In my setup there is a fiber modem (outside the house), a Wi-Fi router, and then all the connected devices.

Oddly, the one that I need to restart the most, seems to be my Mac. Realizing, of course, the problem could still be on the router side, but turning wifi on and off on the laptop usually solves my problem.

I rebooted one device at a time for about a year and made notes about each failure. I didn’t see the pattern until I had done this for a long time.