IP whitelist IPv4

Trying to whitelist my PC to directly access nextcloud hosted on my raspberry pi4 running ubuntu appliance
Anyone know why the whitelist is set up to only allow ipV6 addresses (CIDR format with slashes)?

Not using IPv6 on my router, only IPv4.

or some require the brackets to differentiate from ipv4:

I’d limit the ipv6 range more strictly and wouldn’t rely on the ipv6 disabled on your router (it might be enabled during updates etc.)