It seems like the obvious explanation is that the Pope is not using that altar because there is a pandemic going on, and the sight of the Pope celebrating Mass publicly on the main altar of St. Peter’s is likely to draw a crowd, which is undesirable.
The papal altar at Saint Peter’s Basilica is reserved to the Pope…or on rare occasions, to someone he designates. The papal altar is used for very rare occasions that involve a solemn celebration and many people – all of whom received a ticket from the Prefecture of the Pontifical Household. Masses happening at that altar are of such occasion, they really cannot be “happened upon.”
It’s hard to imagine the amount of work that is required…chairs in their thousands are put in place by the basilica’s work men. An aisle is created by placement of barriers down the length of the basilica.
Those Masses, because of the vastness of the space, requires multiple masters of ceremonies, multiple acolytes and so forth. It is quite a major production.
Even in ordinary times, when a Cardinal residing in Rome dies and the Holy Father chooses to preside, the Eucharist is celebrated at the altar of the Chair which is much more conducive to these types of celebrations which draw fewer people. Everything needed is also right at hand in the sacristy behind this chapel, which is not accessible to the public.
When the first lockdown ended in Rome, the Holy Father celebrated Mass specifically at the altar of the tomb of Saint John Paul II, to commemorate the Saint’s 100th birthday. Pope Francis does that…he uses the other altars, like the rest of us do. That is a wonderful thing, actually.
For those who know Rome, there is no mystery as to why the papal altar has not been being used. Quite the opposite. It is as we would expect, given the situation of the pandemic.
EDITED TO ADD: My response is not a critique of
@Tis_Bearself and her post…her post just gave a point or two that I wanted to specifically address regarding comments of others.
