The Firewall may be part of the trouble, but at least some of the disconnections above are likely due to macOS changing the MAC address of the Wi-Fi interface. By default Sequoia "rotates" the Wi-Fi MAC (media access control) address at frequent intervals.
This is set in System Settings > Wi-Fi > Details... > Private Wi-Fi address. This can be:
Off - it will use the MAC address in the Wi-Fi hardware,
Fixed - it will use a pseudo-random MAC address but keep it the same for that network,
Rotating - it will change frequently.
The trouble with rotating is that a change of MAC address will mess with a) DHCP and IP address and b) the ARP cache on connected devices.
Make sure it is set to Off or Fixed. You will now get a little Privacy Warning triangle - ignore it. The "Learn more..." link doesn't mention the "Private Wi-Fi address" setting.
Apple has not fully thought through the implications of "rotating".