Generally, most pro-social-security people say that all of those are not necessary, not just some.
However, take a look at your first item. How are these immigrants going to pay into social-security exactly, when there isn't a large jobs base to be had? Part of the de-industrialization that the United States underwent was predicated on the notion that if our population was going to shrink anyway, we didn't need that. Now with all those jobs gone and famously "never coming back", bringing in more immigrants to short up a defunct pyramid scheme seems sort of silly.
And as for your second item, where you say "just pay more in" doesn't much jibe with "means tested distribution" where if the government deems you too rich to need it, you don't get it. It really is just welfare at that point, and not a mandatory retirement program we'll all enrolled in. No one has time for that nonsense. Do you have any faith that when the next Trump is in office (which surely will be the case in a few decades, if not much sooner), that you will make the cut for "means tested distributions"? How is that any different than just cutting social security from everyone, if it were to become policy?
