Diamonds seem to be significantly harder to get in the caves and cliffs update. The blobs of ore is smaller, and now I feel I am definitely wasting my time on searching diamonds. I tried many methods on mining diamonds, but I definitely feel that this is not luck anymore. I believe there is a bug in the game. Even by caving, NONE of the caves on the diamond level had diamonds. I played for a good 5 hours on just mining, and I only found a chunk with 1 single diamond. I can assure you that if you know you're game, you should know it should be more common than this.

You are probably going to ask for proof about this. Unfortunately, I don't have real evidence. But what I can tell you is there is definitely a video out on youtube proving this and I did some tests on my own. I went to creative mode and used the fill command to delete the stone and only show ores, even then, I couldn't find a single diamond. The diamonds are actually a large pain to get now. Mining for ancient debris is easier to get than diamonds!!!

Please see if you can look into it.