Wall is somewhat obscure figure, and one of his chief claims to fame is as the first translator of Teilhard de Chardin. He was an enthusiast for Vatican II, to start with, but like many others was disappointed by the results. He wrote in a book published in 1969, reminiscing about his naive earlier enthusiasm for reform:
In those days liturgical reform meant the exact opposite of what it has come to mean since the Second Vatican Council. It meant a purging of the liturgy of hideous accretions—sugary nineteenth-century hymns and their counterparts, mass-produced statues—but also restoring it to its pristine purity of Latin chanted in the Gregorian manner.
You can see more about the book here. I'd link to the Tablet piece, but it is paywalled.
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