Sometimes it's almost comical. Like many of you, doubtless, I make use of those lovely prayers by St. Thomas Aquinas before and after Holy Communion. I have a little card in my Missal with these prayers, which doubles as a bookmark.
The comical part is that all the offending "Thees" and "Thous" have been removed, substituting "You" and "Your," even though ALL OF US continue to use the older form of address in the Our Father and Hail Mary ...
... AND here's the kicker: they still retain the word "VOUCHSAFE"! [There are other even worse translations.]
Therefore, I implore the abundance of YOUR measureless bounty that YOU would VOUCHSAFE to heal my infirmity ..."... and again
I give You thanks, holy Lord, Father almighty, everlasting God, that YOU have VOUCHSAFED to feed me, a sinner, YOUR unworthy servant, for no merits of my own ..."Is this not hysterical?? They keep a word like "vouchsafe," which probably only one in a dozen people understands today, but dump "Thou," "Thee," "Thy" and "Thine"!
Don't get me wrong, "vouchsafe" is a perfectly noble word meaning to "graciously grant" something. My own sense of the language of the prayers in English translation is that it would be much better served by retaining the older forms in toto, rather than trying to modernize them and throwing a philistine indignity like "YOU" in amidst the dignified references to "almighty" and "everlasting" and "imploring" God's "measureless bounty."
Keep "YOU" for the ordinary language of today. Keep the language of prayer noble, elevated, respectful, and dignified. "Hallowed by THY name. THY kingdom come. THY will be done ... Blessed art THOU among women, and blessed is the fruit of THY womb, Jesus."
Related: David Mills, "Lewis & Orwell on Language" (Patheos, July 9, 2014).