Yes they were always going to phase out T'Challa.
That's why they gave Shurri T'Challa's comic intelligence (being one of the smartest). Shurri is actually closer to the T'Challa of the comics than Chad's T'Challa was.
If Chad didn't pass, Black Panther 2 would have been about T'Challa reconciling with his young son and needing to make up lost time, with Shuri also becoming a Black Panther.
Now you only give superhero characters a young child in a sequel movie to PHASE THEM OUT.
I told y'all that T'Challa in Black Panther was
and a damn supporting character.
Think about it. How the fukk do people come out of an entry Black Panther movie with the discussion being about Killmonger and NOT T'Challa?
T'Challa should have been presented as the most dominant person intellectually, economically and physically in the room AT ALL TIMES. If they did that we would have got a recast. Instead he was made to be NOTHING without the suit, LACKED his intelligence and strategy mindset and had to be told what to do
It's why Blade was so good, Blade WAS THE MAN, the ACTION HERO and the movie was PROUD to have it that way.
"some motherfukkers are always trying to ice-skate uphill"