Respectfully, it's about the political dangers of not being unified. Rights lost are almost always gone forever. And it's the salami-slicing of those rights away that eventually leads to the shocking gun bans and confiscations in places like Australia, the UK, and, IIRC, NZ as well.
And this issue specifically is absolutely perfect as a trojan horse for a gun-ban workaround.
In the US they've had increasing difficulty in getting around our 2nd Amendment in the courts and in legislatures across the country. Banning ammo and banning shooting on public lands are absolutely, explicitly part of their agenda on forcing more gun control, to get around this.
It starts with banning lead shot on waterfowl. Then lead ammo in specific zones of California. Then lead ammo bans for all hunting across California, and now certain federal lands. This has already happened. And it is a relentless march by the left.
Next steps are bans on all lead ammo on state lands, one by one. And bans on lead ammo on all federal land. This a very easy leap for them to argue, because "lead poisoning" and how easy it is for everyone to believe shoddy science. And each is just one more salami slice, one election cycle at a time.
Once lead ammo is banned on all federal and state lands, the next step would be bans on copper bullets - because, frankly, copper is a heavy metal too. But the bans on ammo types and shooting on public lands aren't the reason it's pushed politically - that reason is further gun control.
So the issue isn't about who cares what you or other hunters use - the issue is making sure any "science" around the issue isn't politically motivated with biased agendas, to further take away our rights. I happen to live in a vast, remote part of America, in a state that is owned 87% by the federal government. Nevada. This is a real threat to my freedom and that of all of my descendants to come, and it's fueled by radical agendas, weaponized by biased and politically driven "science", and aimed at voters who don't know any better.
It's dangerous as hell. And that's why it matters.