I've noticed wheat does not provide the expected output of seeds.
When reading a minecraft wiki, breaking a wheat block should be expected to yield 1 wheat crop and 1-4 wheat seeds.

Though I acknowledge a wiki is not right about everything (possibly the wiki I read is for java edition), this is still a noticeably low drop rate for seeds, making it hard to farm wheat, and I wonder if it is working as intended.

I performed some tests:
64 blocks of farmland fully grown with wheat yielded
Test 1: 64 wheat and 95 seeds
Test 2: 64 wheat and 94 seeds
Test 3: 64 wheat and 106 seeds
Test 4: 64 wheat and 95 seeds
We may observe that wheat adds up 1:1 consistently, but seeds are at 256:390, meaning sowing one seed will yield 1½ seeds, approximately.

I also tested individual farmland blocks with wheat. I counted the amount of seeds yielded by breaking the wheat block. I found the following occurrences over 64 individual blocks:
Yield 0 seeds: 6 occurrences in 64
Yield 1 seeds: 17 occurrences in 64
Yield 2 seeds: 34 occurrences in 64
Yield 3 seeds: 7 occurrences in 64
Yield 4 seeds: 0 occurrences in 64
It would seem that wheat, when broken, yields 0-3 seeds, not 1-4.