We restarted our realm with the 1.17 update a couple of days ago and i have only found diamonds 3 times in 7+ days that i have been on.  And i have noticed how small the deposits are (only 2 per vein i found). I have went and opened up a creative new world and went into spectator mode and it is true, there isnt any significant amount of diamonds. I believe it has something to do with the spawn depths being changed in game script while the actual world depth stayed the same. I hope this gets resolved quickly because at this rate (ive been digging for 10 hours and found 6 diamonds while breaking doesens of iron pickaxes) its not worth playing