I don't know if I'd go for "more capable" then previous showrunners since past shows had T'Challa clean the clocks of the entire team when he first met them and be their most effective member (EMH) while past seasons of Assemble had him still be as uber-competent as ever.
I don't know if Cap is really a character I'd say have any character protection on these shows unless you're under the thought process that Cap should be outclassed by anyone he's on a team on. I'd say Cap is handled as fairly as any other character in terms of portrayal, although maybe he's not as prone to plot-induced stupidity and inconsistent characteirzation as certain other characters (Cough)Iron Man, Hawkeye (Cough).
I'm sure Black Panther will continue to be a main member of Avengers team's moving forward, although I suspect his appearances will not all be exactly like his depiction in the current cartoon unless they have him as the leader (which necessitates him getting more screentime and lead character status compared to other team members).And of course now that BP has his elite-level popularity, it's now in the best interest of many to cater to the character in general. Hence Aaron's current Avengers run and likely any future Avengers cartoons and movies in the next MCU phase.
It being Zanda in disguise is the only way it makes sense how she could so badly misinterpret what happened to Cap.
Characterization is probably a factor too. EMH T'Challa was a very zen and humble individual, who was a king and Avenger very early into his career, so I think how he reacted or played into the team would be different from Redjack's Panther who was a king longer and had a different dynamic with the team and has more of an edge to him.
Although contrast that to the Secret Invasion arc where he had a longer tenure as both king and Avenger and then basically abandoned the team for Wakanda once the Skrulls were revealed.