No. She sued Disney because they were screwing her over by releasing Black Widow on streaming earlier than in the theaters to get out of paying her what she's owed. Talent gets paid certain royalties for theatrical releases but not for streaming. Disney was trying to screw over their actors by making it funneling traffic to Disney+ and refusing to pay her. She took on House of Mouse and essentially won as they settled out of court.
Honestly, and this is just prospective theory, I think ScarJo pissed off Disney by taking a moderate stance and for virtue of being a white woman. She championed the non-woke stuff sooner than anyone else and then Disney (I'm guessing, I have no proof) apparently pulled her aside and told her to shut her damn anti-vaxxer mouth and threatened to blacklist her. That's why immediately after while promoting Black Widow, she did a complete u-turn and went full Hollywood Woke Shill after years of saying the opposite. She probably pissed off the wokesters at Disney for a long time. That's why when her contract with Marvel was up, they just straight up killed Black Widow. Nobody else got that treatment. Nobody else is permanently dead in the MCU. Just ScarJo. Especially now that Doomsday is coming around and we see all these old MCU stars returning, Scarjo is notably absent and has not had any mention of her yet.