"You do understand that you have no options, outside of eliminating immigration, right?"

Even a "forever" ban on new immigration is no guarantee of fixing the situation with the demography and birth rates being what they are. It would be a band aid on a gun shot wound.

1) This option has been examined and dismissed by most in the Alt Right. Interestingly Germany is now offering to pay Muslim Migrants to return where they came from so we'll actually get to see how successful such a venture would be without trying it ourselves in the United States.

2) As you said ethnic cleansing via forcibly removing people and/or killing them is costly and bad optics. However this is always the fallback option. It has to be. We have a right to defend our homeland and that includes with deadly force if necessary. We don't want it to come to this though obviously.

3) This is Jared Taylor's preferred solution. He seems to have given up on ever taking back an actual white nation in North America and instead just wants whites to live peacefully by themselves if they choose to do so. It's a nice thought but it will never be allowed to happen. When whites out perform non whites they cry racism and discrimination and demand the benefits of white work be it in the form of welfare or housing opportunities. They want to live in low crime neighborhoods (formed by whites) but then they shit it up once they get in. There is no escaping "diversity" if you're white. This is not an option.
And that’s not even counting that no liberal and most conservatives are not going for the first two options for moral reasons. Even if people became „woke“ and you would make 1 or 2 work, it would still divide people more than you would unite them.

In case you haven't noticed both liberals and conservatives are becoming increasingly irrelevant.

"And lastly – 35% of legal US population is not white and the number is going to increase, even if you can get rid of immigration. So ultimately, US won’t become white nation ever again."

I'm sure they said Spain would never be Christian again right before the Reconquista. They, whoever they are, probably think Constantinople will never be retaken. They were wrong then, they are wrong about the United States now, and we will prove them wrong again on the shores of the Black Sea before they can even figure out what happened. Deus Vult!