I use you example, slightly modified;

package main

import (
	"log"

	"github.com/moby/ipvs"
)

func main() {
	handle, err := ipvs.New("")
	if err != nil {
		log.Fatalf("ipvs.New: %s", err)
	}
	log.Println("ipvs.New did NOT give an error!!")
	_, err = handle.GetServices()
	if err != nil {
		log.Fatalf("handle.GetServices: %s", err)
	}
	log.Println("handle.GetServices did NOT give an error!!")
}

And run on a kernel where ipvs is not configured. Output:

# moby-example 
WARN[0000] Running modprobe ip_vs failed with message: `modprobe: WARNING: Module ip_vs not found in directory /lib/modules/6.1.0`, error: exit status 1 
ERRO[0000] Could not get ipvs family information from the kernel. It is possible that ipvs is not enabled in your kernel. Native loadbalancing will not work until this is fixed. 
2022/12/23 18:09:43 ipvs.New did NOT give an error!!
2022/12/23 18:09:43 handle.GetServices did NOT give an error!!

So, that ipvs can't be loaded is obviously noted, but even so err==nil is returned.

This is a serious bug, which enforces weird work-arounds do detect if ipvs can be used:

https://github.com/Nordix/kubernetes/blob/68d78c89eccf2d2f381033c836472d53f3ba41c9/pkg/proxy/ipvs/proxier.go#L692-L694

The active and inactive connection counters are represented by 16 bit unsigned integers in this library, even though they are returned as 32 bit values by the system. This leads to a rollover of values if more than 2^16 = 65,536 connections exist for a destination. See #24 for a fix.

A lot of Kubernetes users (using IPVS proxy) run on CentOS 7 which is based on Linux 3.10. In the past there have been compatibility issues with older kernel where certain netlink attributes do not exist. For example, for Linux < 3.18 the address family doesn't exist so we had to create some workarounds (#15 and #19). The address family compatibility issue would have been caught if we ran tests on CentOS 7.