moviesCollection.find(queryFilter).iterator().forEachRemaining(results::add); vs moviesCollection.find(queryFilter).into(result);)

Approach 1:
moviesCollection
.find(queryFilter)
.iterator()
.forEachRemaining(result::add);

Approach 2:
moviesCollection
.find(queryFilter)
.into(result);

So far, you have completely neglected to point out why you use approach 1 sometimes and approach 2 at other times.