In The Teaching of the Catholic Church by Canon George Smith (1960), it states regarding Baptism of Desire that "today it is the opinion of all theologians": The Teaching of the Catholic Church; a summary of Catholic doctrine : Free Download, Borrow, and Streaming : Internet Archive p382-385
It is interesting to read the account of the funeral oration of St Ambrose for the Emperor Valentinian who died a catechumen before he could be baptised by St Ambrose: He heard people expressing regret that the Emperor died without baptism: "Will he not then receive the grace which he desired and obtain what he asked for?"
"Today" it is the teaching of all of today's theologians. Same as the NO is taught by all the bishops in union with the pope. The only thing that actually proves is unanimity in error.
Too add a little balance, a snip from Brother Francis......
"...If "Baptism of Desire" was something contained in the "deposit of Faith" and part of the Apostolic doctrine, why then would these faithful be grieved that Valentinlan had not been baptized with water?
The reason these faithful were grieved was because they believed that "unless a man be born again of water and the Holy Ghost he cannot enter the Kingdom of God." Perhaps too, they had been Instructed by Ambrose himself, who said:
'One is the Baptism which the Church administers: the Baptism of water and the Holy Ghost, with which catechumens need to be baptized . . . Nor does the mystery of regeneration exist at all without water: 'For unless a man be born again of water and the Spirit, he cannot enter into the kingdom.' Now, even the catechumen believes in the cross of the Lord Jesus, with which he also signs himself; but, unless he be baptized in the name of the Father, and of the Son, and of the Holy Ghost, he cannot receive remission of his sins nor the gift of spiritual grace." (De Mysterlls,-THE DIVINE OFFICE)..."