Though he originated the character in the MCU, actor Hugo Weaving didn't reprise his Captain America role as Red Skull for Avengers: Infinity War and Avengers: Endgame - and it turns out the reason is as simple as not wanting to renegotiate his contract.
"Oh, yeah. I loved playing that character Red Skull – it was a lot of fun. We were all obliged to sign up for three pictures: I was thinking [Red Skull] probably wouldn’t come back in Captain America but he may well come back as a villain in The Avengers. By then, they’d pushed back on the contracts that we agreed on and so the money they offered me for The Avengers was much less than I got for the very first one, and this was for two films," Hugo told Time Out London, referring to Red Skull's appearances in Infinity War and Endgame. "And the promise when we first signed the contracts was that the money would grow each time. They said: 'It’s just a voice job, it’s not a big deal'. I actually found negotiating with them through my agent impossible. And I didn’t really wanna do it that much. But I would have done it."
In the end, actor Ross Marquand took on the role for the pair of cameos in which Red Skull appears as the keeper of the Soul Stone on Vormir, impersonating Weaving's distinct voice and mannerisms as the character.
Weaving also confirmed to Time Out that he won't reprise his iconic role as Agent Smith in the upcoming revival of The Matrix either - though that came down to a scheduling conflict.
"The Matrix is a very different story. It’s unfortunate but actually I had this offer [for The Visit] and then the offer came from The Matrix, so I knew it was happening but I didn’t have dates. I thought [I] could do both and it took eight weeks to work out that the dates would work – I held off on accepting [a role in The Visit during that time]. I was in touch with [director] Lana Wachowski, but in the end she decided that the dates weren’t going to work. So we’d sorted the dates and then she sort of changed her mind. They’re pushing on ahead without me."
It's unclear if a different actor will portray Agent Smith - a computer program that could assume any appearance - in the new Matrix film, which is scheduled for a May 4, 2021 theatrical release.