If you put on a resource pack that changes the text in en_us.json file, the game doesn't seem to take the en_us.json file into account, and it'll revert back to the regular text.

For example, if you have a resource pack that changes the name of "Iron Ingot" to "Steel Ingot" or something, the game won't seem to see that and will read it as "Iron Ingot" like normal.