I heard a sermon online recently that claimed the inscription Pilate had placed on the cross, "This is Jesus, King of the Jews", INRI in Greek, in Hebrew actually translates to YWVH. Is this true? Is that why the religious leaders were so upset? Was it simply the claim "King of the Jews" that upset them, or the fact that in Hebrew, the letters stood for Yahweh? The passage in question reads, "Pilate also wrote an inscription and put it on the cross. It read, 'Jesus of Nazareth, the King of the Jews'" (John 19:19).
INRI isn’t Greek. It’s Latin: Iesus Nazarenus Rex Iudaeorum, Jesus Nazarene King of Jews. There is no YAHWEH here. (The consonants are YHWH, or YHVH if you're German.) Probably the person you heard this from hasn't had the benefit of studying Hebrew, Latin, or Greek. So no, YHWH is not the same as INRI. They aren't even close!
And what about the religious leaders? They were upset because the official charge on the titulum read like a proclamation. They denied that he was their king – “We have no king but Caesar!” (John 19:15). This is similar to Caiaphas' "prediction." This high priest said "Nor do you understand that it is better for you that one man should die for the people, not that the whole nation should perish” (John 11:50). That makes the titulum the second comment pointing to Jesus' true identity as Messiah coming from pagans.
Note: Because I had the privilege of studying 10+ years of these languages, it's usually possible for me to clear up questions like yours. I love ancient languages. Yet to learn them, it takes years of university-level study. It's not wise to "dabble" in Greek or any other language -- or subject -- if you're presenting yourself as an authority or your opinion as linguistic or historical fact. The caution of Alexander Pope is apropos: "A little learning is a dangerous thing / Drink deep, or taste not the Pierian spring."