Google Places supplies at most five reviews selected and ordered by Google for relevance, so Steuard cannot load every review or request the five newest reviews from that source. This is an API limitation, not the block's Maximum reviews setting.
The Maximum reviews and Minimum rating controls can reduce the supplied set further, and moderation can hide individual cards. They cannot expand the set beyond what Google returns.
Your overall Google rating and total review count still represent the business-level values returned by Google; they are not recalculated from the visible cards. See How does review moderation affect cards, ratings, and schema?.
