Why should we use method Resferences instead of both?

Question

When passing functions as argument to high-order functions, we can usually use two different Java 8 mechanisms+:

1. Lambas:

var averageLength = stringList.stream()
    .filter(s -> s != null)
    .mapToInt(s -> s.length())
    .average();

2. Method of reference:

var averageLength = stringList.stream()
    .filter(Objects::nonNull)
    .mapToInt(String::length)
    .average();

By default Intellij IDEA recommends replacing Amble for method References (even when the code becomes slightly more extensive as in the example above).

My question is, why is it recommended to use method References instead of Amble? Is it a purely legibility issue? Reuse? Performance?