Summary
As of Java snapshot 21w17a, copper mining has changed. Now by mining copper ores, it drops 2-3 raw copper instead of just one. On Bedrock however, it hasn't changed. This breaks parity between the editions.

Step to Reproduce
1. Place down copper ores and deepslate copper ores.
2, Mine it using an unenchanted, at least an iron pickaxe.
---> It drops only one raw copper per ore.