Having dealt with incensed customers with this same complaint, I can understand the confusion. All of Apple's tech specs/naming conventions are by year introduced, but the Store doesn't refer to these, unless you're on the refurb site. It's worst for mid to late year year updates, where someone has purchased a 2019 model in June 2020 (for example) and is incredulous that About this Mac lists it as the 2019 that it is.