The daft thing is, those that bemoan most about immigration are often those who also denounce climate change.
But refugees from war, economic migration etc will all feel so insignificant once climate migration begins.
Even if you think the planet goes through these cycles regardless, there is enough scientific evidence to prove that humans have had an impact on speeding the process up somewhat and we can have an impact slowing it down again.
The argument of all or nothing seems silly to me, but hey ho.