Allays in Java edition only see items they're supposed to pick up within a range of about 6-8 blocks, the details are uncertain. This range, in comparison to Bedrock, is astronomically smaller.
In Bedrock, Allays can detect items they're supposed to gather within a range of at LEAST 40 blocks, possibly more, and will fly toward it immediately and back.
1. Set up a situation, probably with a dropper, in which an Allay has to pick up an item on Java edition from a great length; 40 blocks out.
2. The Allay will take no notice, and only go to grab it as you move very close to the item
3. Try the same thing on Bedrock; the Allay will be able to see the item quite far away and will go to collect it.
The attached videos demonstrate this behavior difference in each version.
Important details as of 22w18a and Beta 184.108.40.206:
Bedrock Item Detection Range: 64
Java Item Detection Range: 32