There is a strong need for accuracy when it comes to adaptations and stuff and there’ll be some mistakes every now and then. Using still-existing real life or contemporary, if unlikely examples isn’t perfect like say basing medieval Irish cat ownership on contemporary French, German or Russian cat ownership but does give a better idea of what it’s like or could’ve been like.
Same thing goes for real life versions of race-bent fictional characters. Given the furore over black Wally West (now an angry, fast street kid), Usain Bolt comes closest to what readers expect of him in character. Outgoing and fast. At least that’s the public perception of Usain Bolt but he gives a better idea of how black Wally West should turn out to be in some regards.
Given the expectations of Wally as an outgoing white bloke, Bolt’s the closet thing to it in real life in a way. Not perfect but close enough to be believable.