Similar functionality is provided in nftables for linux ('inet' filter applies to both ipv4 and ipv6). But, outside of the most trivial use cases of just block

Similar functionality is provided in nftables for linux ('inet' filter applies to both ipv4 and ipv6). But, outside of the most trivial use cases of just block/allow a port, it doesn't really work out to be that useful because of other restrictions. E.g., if you are collecting IPs that have e.g., created new connections to some set of ports greater than n times within a time period to rate limit them, you are out of luck and will need separate rules for ipv4 and ipv6 since you cannot save a mix of ipv4 and ipv6 addresses to the same list.