A contract's only as enforceable as whatever consequences of a breach can be mobilised.
All I see is two brigades of lawyers, one probably much larger than the other, working out the margins.
Disney would have been advised to wear the legal and economic risk of streaming BLACK WIDOW early for commercial reasons, with Johansson's counsel then doing their bit to defend her end of the contract.
Disney is not a person who displays good or bad conduct, and Johansson's business setup is not a person either, really, though you can imagine the actor taking this personally.
The streaming thing is the state of the industry and its revenues, Villeneuve is supposed to have had to fight tooth and claw to get DUNE a proper theatrical entrée before it gets distributed more broadly.