Hussar
Legend
It might not be irrational or hypocritical, but, it is pretty thin. After all, it's not like the DM is asking permission beforehand. I seriously doubt any DM in their session 0 straight up tells the players, "Hey, from time to time, when I feel it's appropriate, I'm going to fudge die rolls. I'm not going to tell you when, but, I am going to do it". I'm pretty sure what the response from the players would be and it likely wouldn't be very positive.I do have to point out you can think its ethically OK but think there's a loss of something in the illusion of the game if its visible. I don't consider that a good enough reason, but its not an irrational or hypocritical one.
Because, once you've made it clear to the players that you might, at any point in time, whenever you feel it's "appropriate" over rule the dice and any time you do it, you will not tell the players, you lose a fair bit of trust at the table. After all, they never know when you will do it, so, that makes every roll suspect.