The Sacralist model of the Church has never been much for Church Discipline... that is with regard to those who at least nominally hold to the paradigm.
If you reject it, then in the Sacralist system you're a theological and socio-political threat and when given the political ability, the Sacralist powers both Roman Catholic and Protestant were and are quite eager to destroy you.
But generally speaking if you're not too immoral and you don't speak or campaign against the paradigm you can remain in good standing.
Rome's 'Big Tent' approach to catholicity has on the one hand pulled off an amazing feat. They have managed to keep together a massive institution with widely divergent beliefs and power-centers. The tent is so big it's in danger is disintegration. The margins are so wide, that the centralised power in Rome has trouble enforcing any kind of standard with regard to doctrine and morality.
Many are arguing it has gone too far. There has to be a correction. Benedict XVI tried to start the course of action and met massive resistance and in the process began to discover just how dirty, corrupt and wicked the Roman Entity really is.
There's a fear in tightening the noose, in beginning to enforce discipline. Joe Biden is obviously not a Christian. He's a wicked man on many fronts and yet still 'could' be a 'good Catholic'.
But he's not even that and in addition to his embrace of American heresies, lies and militarism he's a Sodomite.
He may not personally engage in such practices but he approves of them, celebrates them and encourages their practice. He is under the same judgment according to Romans 1.
The provided link argues something must be done. He has to be called out and challenged. He must be formally disciplined. His continuation as a Catholic in good standing makes a mockery of the Church's Authority.
Americanism which is the religion of most Catholics and Protestants in the United States chafes against religious and ethical authority or any authority outside the self. People don't want to be told they're sinners in need of repentance, they don't want to be told their wrong and refuse to accept that they can't do whatever they feel is best... regardless of Church doctrine. They don't want to be told they don't get to decide everything.
Catholicism doesn't have much of a leg to stand on at this point. The appeal is made to the authority of a long tradition. Well, it only takes a few moments of inquiry to learn the narrative doesn't hold up very well and the organisation is riddled with hypocrisy on a scale that surpasses even the worst of governments and corporations... of which Rome is both.
If Rome stands up to Americanism and begins to challenge its premise by disciplining someone like Biden there's a real warranted fear that the backlash against the hierarchy will be fierce.
Catholicism is in a slow decline but even those numbers are somewhat misleading. Most Catholics aren't attending church and the majority of them do not adhere to Catholic teaching. It's rare to find someone who does. In addition they are in a crisis with regard to the priesthood. They cannot get enough young men to sign up. They laicisiation of Roman parishes also breaks down authority. Rome may not ordain women, but it's a lot of older women who are essentially running local parishes.
There's a growing anger and frustration with Rome regarding its official positions and the numerous scandals. Financially Rome is paying out millions of dollars to abuse victims leading to the closing of many dioceses.
The long-term demographics are not positive. Rome is following the same pattern exhibited in Protestantism... their young people are walking away and not coming back.
If Rome begins to assert its authority it will probably see a mass exodus but if it continues to let people like Biden flaunt its authority, then Rome's authority is destroyed and eventually it will become a meaningless organisation that allows people to pursue their own spirituality while trying to funnel money into helping the poor etc...
At this point many Catholics stay in the bosom of Rome due to tradition and superstition. They have abandoned its authority and as long as the hierarchy stays docile, they'll stay in and nominally participate. But if Rome starts to demand compliance, then many of these same nominal Catholics will jump ship.
The fall of Rome is not something I lament but it's interesting to watch.