That happened back in November 2021. It was introduced here.
In Google's words:
Going forward, we'll be more precise with our wording when differentiating systems from updates. Yes, we'll still have things like a "helpful content update" or a "product reviews update," but when possible we will explain those as updates to the respective systems, such as the "helpful content system" and the "product reviews system." We'll also be refreshing our help pages to reflect this terminology change, over time.