The obvious job is social proof on the product page, and both platforms do it: star ratings near the title, review content further down, customer photos showing the product in a room or on a person rather than on a studio background.
The less obvious job is structured data about your own catalog. When the review form asks how a garment fits, how strong a scent is, or how a tool held up after a season, the answers become filters on the page, copy for the description, evidence for the buying guide, and segments for email. They also tell merchandising which variants disappoint before the returns rate does.
Both platforms support attribute questions. What differs is how much you plan to do with them. If review data is going to feed segmentation and merchandising decisions, weigh how the attributes flow into your email platform and reporting, not just how they look in the widget.