it's a black man who undeservedly took a white man's place and assumed his identity

It's even better than that as per the Netflix show "Falcon and the Winter Soldier". Sam/Falcon initially doesn't take the shield, he donates it to a museum and then the US Government take the shield and give it to John Walker/US Agent. After a lot of shit goes down Falcon takes up the mantle at the end but a lot of the problems that occur would have actually be avoided if Sam had just manned up and took the fucking job like Steve asked him to. Someone could possibly make this into an allegory for a black man running out on his responsibilities only to come back later to a mountain of shit on fire but then I'm far too cynical to do it myself these days and would rather just cut straight to the point and state how badly the writers made Falcon because the meme fits that fucking much.