I haven't seen Tenet or the movie he did with Zendaya so I only know him from Ballers and the Spike Lee movie so he didn't scream T'Challa to me plus there was a pic posted here I think and it showed that he was the same height as Zendaya.
Before he was cast as Hawkman, Aldis Hodge topped list as worthy replacements to recast as T'Challa