Is it really a mystery though?
The US legislative branch is terrified that impeaching a sitting justice would de-legitimize the Supreme Court. And of course now, he is protected by the fact that so many of the SC nominees apparently lied about Roe v Wade.
I don't know that I could equate the "I

stare decisis" game to sitting in a chair under oath, saying that a woman was lying about sexual harassment and claiming under oath that you didn't do what she said and you didn't talk about Long Dong Silver, etc.
If you or I were caught perjuring ourselves, we'd be under investigation and possibly sent to prison.
It's bad enough that Thomas was a sexual harasser. But how can someone who perjured themselves about sexual harassment be considered appropriate for the highest judicial body in the country?
If there were a do-over, the allegations about Thomas should have come to light during the Appeals Court nomination process when Thomas was put on the DC Appeals Court to replace... wait for it... Robert Bork.
It is why they didn't convict Trump during impeachment. It would have damaged the dollar and US standing.
The first impeachment, perhaps. The second impeachment was after he had been given the boot and after he fomented an insurrection against the certification of an election by Congress.
It's really a measure of how low we've sunk that we have to distinguish between which of the impeachments we're referencing.
The reality is that the richest and most powerful people in the country, who helped make sure most of the conservative judges were appointed likely interceded to make sure that the senators and congress reps they own don't make a move.
They would prefer to go along to get along, making deals and getting rich.
Each time I look at all of the SCOTUS hearings since Bork, I'm reminded about how many hours of work and how many millions of dollars have been put into putting "originalist" justices into the Court to try to remake the Court into the image of multi-millionaire donors and evangelical activists. And these same evangelicals have to nerve to talk about "grooming"?
These Court-tampering PACs and their front groups like the "Federalist Society" start looking for candidates in the top tier law schools. They get them into internships with Federalists judges. They get them nominated to Federal Courts.
They funnel money to friends and family members of the justices, including the wife of the Chief Justice.
They wine and dine them and give money to the Court's "historical society".
The opinion polls about the Courts indicate that the American public doesn't agree with the tampering that has gone on with the Courts.
Do you approve or disapprove of the way the Supreme Court is handling its job? In general, do you think the current Supreme Court is too liberal, too conservative, or just about right?
news.gallup.com
At this point, rehearing the Thomas witnesses would provide both an accountability for a Court that is falling in reputation with the American public and it might also provide penance for Biden to correct the perception that he gave Thomas a pass on the sexual harassment accusations.
Oh... put a pin in this for future deplorable discussions about getting favored cases in front of Uncle Thomas:
The bill could allow county clerks to deny marriage licenses to same-sex, interfaith, or interracial couples in Tennessee.
newrepublic.com