> At exactly the same time they say "we can't reduce migration, we have an aging population". That is not replacement theory because......? Uh?? It is different?!

Some on the left (myself included) consider ourselves both immigrants and native. And see immigration as a net good, even if it is offsetting a declining 'native' workforce. At least in the US few can claim to have ancestors from their own town going back thousands of years. And if they some can, IMO that's not necessarily a virtue.

My ancestry records go back a few hundred years and is a blend of people from a variety of countries (at least one no longer exists, good riddens because it was a mess) and a couple different continents. My kids have a parent from another country. This only makes us stronger IMO.

Of course too much immigration too fast can entirely replace a nation. That is tragic and worthy of concern, especially if done without consent. But not even the far left is calling for that. Biden was poised to sign the strictest immigration and border policy ever proposed by a democratic president. And it was Trump that put a stop to it. Because those in power on the right aren't interested in pragmatic or real solutions. They want an issue they can leverage forever, like a carrot dangling in front of a mule, to steer it wherever they desire. Hence their made-for-TV theatrics with Dr Phil and photo ops at the extraordinary rendition centers.