This topic recently came to my attention again, and it prompted me to look at one of the traditional books on the matter, Peter Anson's Churches: Their Plan and Furnishing (1948). The whole set of chapters on altars is very interesting, but for brevity and the interest of readers, the following excerpt from chapter 6 captures one of the striking flaws (and, I add, novelties) of the Immaculata altar. Namely, the lack of a baldacchino or some sort of canopy. The lack of this canopy, which also provides a necessary vertical element to the altar, is why so many traditionalists have an intuitive sense that this altar is a "Novus Ordo table." The issue isn't that it is detached, as all the altars of the Roman basilicas are, but that it lacks a canopy, which all Roman altars include. As I said before, the modernisers removed canopies as quickly as possible because the vertical element was a visual reminder of the transcendent nature of the Holy Sacrifice; when you remove it, you flatten the Mass to the communal "meal" that they wished to create.

The idea of the apse murals and surrounding columns (without any cover) constituting the vertical element of the altar or a canopy is completely novel in Catholic tradition and would have obviously been rejected by the Sacred Congregation of Rites as satisfying the liturgical norms.

Further, Father in the video refers to how the old requirement of a baldacchino was done away with, but as the author below shows, he conveniently ignores that many liturgical authorities considered that the requirement still applied to the high altar and Blessed Sacrament altar. We find this so often among SSPX priests: they pick and choose what constitutes tradition and hence are "cafeteria traditionalists."

The excerpt:

The Sacred Congregation of Rites laid down in 1697 that every altar should be covered with a civory or canopy. More recently (in 1846), that at least the altar of the Blessed Sacrament should be so respected. However, the editors of the General Index of the Decrees of the S.R.C. and certain modern liturgical writers maintain that, owing to the widespread neglect of this discipline, even in Rome itself, these decrees no longer bind. On the other hand, many authorities insist that the decrees are still in force for the high and Blessed Sacrament altars.

It is still the mind of the Church that a civory is the best way to emphasize the dignity and majesty of the altar as representing Christ Himself. Geoffrey Webb reminds us that a canopy "is the most effective way of expressing honour due to royalty; and there is nothing which can replace it as the most expressive manifestation of the Altar's true dignity and majesty." Van der Stappen explains this principle: "The mind of the Church is that over all altars should be constructed a civory on columns, or a shrine of wood or stone or marble or, in the absence of a canopy (i.e., civory) on columns, should be hung a canopy which they call a baldaquin, square in shape, covering the altar and its footpace. If a (civory) on columns, or a baldaquin of this kind is fitting over any altar, it is certainly most of all fitting over the altar in which the Most Holy Sacrament is reserved; and not only is it fitting, but the S.R.C. has established that a baldaquin should definitely be placed."

[...]

In view of the wide-spread neglect of the rules laid down about canopies over altars, it cannot be insisted too strongly that even the most simple church, where the Blessed Sacrament is reserved, should not be without some form of canopy over the altar. Cardinal Schuster writes: "In the minds of the early Christians the Altar could never be without the halo of its sacred nature—that is, the Ciborium or Baldaquin in marble or in silver. The Altar in its entirety constituted the true Tabernacle of the Most High, who assuredly could not dwell sub divo without a special roof of His won under the lofty vaulting of the naos."