Can it be said that using a generator reduces memory consumption, while an iterator does not?

Yes, you could say that, but with some clarifications.

Generators in Python produce values one at a time, "lazily", without storing the entire sequence in memory. This helps save memory when working with large or infinite sequences.

Iterators, on the other hand, are a general interface for sequential access to collection elements. An iterator can be implemented as a generator (lazily) or as an object that stores the entire collection in memory.

Example of a generator:

def count_up_to(n):
    i = 0
    while i < n:
        yield i
        i += 1

This generator does not store the entire sequence in memory but yields one value at a time.

If an iterator is based on a list, then the entire list is stored in memory.

Thus, generators usually reduce memory consumption compared to a regular iterator, which can store all elements at once.