Can you explain why you think each of those are somehow centrist or "fake progressive" (lmao)?
And please enlighten me on how Bernie is a sure-fire win. Forgetting for a second about your/my opinions on him as a candidate, many people would argue that he's by far the riskiest choice for a number of reasons. It's telling that (despite his name recognition and insane lack of scrutiny so far) he has been consistently crushed in the polls by a guy who hasn't even announced his candidacy.
People have already done a great job in this thread explaining how all of those candidates are not progressive so skipping.
Bernie is the strongest because he has (1) Universal Name Recognition AND Universal Platform Recognition (2) The most boots on the ground, the most robust 50 state infrastructure-- a network of support from Our Revolution, Unions, and progressive organizations like Justice Democrats, Sunrise, DSA, etc. (3) That infrastructure comes with the most dedicated base that will put in the most work (4) He outstrips all his corporate competition at the ability to raise funds (5) Tons and tons of organic/earned attention both because his supporters have the loudest voices (making content all over the internet...) and his critics from the mainstream media are the loudest too (which in turn fires up the base more)-- this is massive in marketing terms, because Organic/Earned >>>>>> Paid in terms of engagement and conversion-- this is essentially how Trump won in 2020-- not to mention the biggest social media following. (6) The most reliable, trustworthy record. The whole last few pages has been all about whether a candidate is trustworthy or not; and every candidate in the race is a (???) except for Bernie in terms of what their real agenda is. Bernie being a known quantity is part of his strength-- while every other candidate will be fighting to keep loyalty from their supporters, Bernie's is pretty rock solid, because Bernie's doesn't trust anyone else. (7) He's the most popular public servant in the country. This helps massively in a crowded field.
I could go on, but that's enough.
As to why Biden is running higher-- it's because Bernie is a known quantity and those who know he is in their economic disinterest, or simply aren't comfortable with him have a solidified opinion reflecting in the polling and his disapproval ratings. Biden has been off the radar and people kind of forgotten who he is. Bernie's approval/disapproval ratings are largely based on substance; Biden's approval/disapproval is largely nostalgia.
But when they start digging... that he was a writer for the crime bill, a writer for the patriot act, a writer for the bankruptcy bill, that he voted for NAFTA, voted to eliminate Glass Steagall, voted for the Iraq war, he was the candidate of credit card companies, he was against busing integration... that his legislative history is directly connected to our bloated prison population and broken criminal justice system, NSA spying and lost constitutional liberty, the credit card and student loan debt crises, the deregulation of wallstreet and 2008 crash, the towns falling to ruin from lost manufacturing jobs, and the sons and daughters who never came home from our endless wars...
...Joe Biden has been on the wrong side of history at every point in modern history (where Bernie was almost always on the right side of it), and has been a key player in politics that has been more devastating for the American people on an order of magnitude greater than the entire Trump presidency.
JOE BIDEN'S POLICY RECORD IS TO THE RIGHT OF TRUMP, and pretty significantly so. The politician who's position record correlates most closely with Biden's is Ronald Reagan.
We are looking at the most politically engaged era in generations and truly fired up progressive wing. The Democratic voters have 70-90+ approval for Medicare for All, A Green New Deal, Raising the Minimum Wage, Free College Tuition, etc. Biden's candidacy has zero chance of victory just based on substance before you get to the fact that he's an awful campaigner who has started strong and crashed and burned out twice on the Presidential campaign trail already.
Think of it this way-- Bernie is polling on an entirely different level from Kamala Harris etc. even when all his enemies know exactly who he is and why they dislike him; when the haters have already reached maximum hatred for him.