Your math is off. Traditionally the studio that created the film gets 55% of ticket prices, whereas the theater gets 45%. So if Disney were to release a film direct to
Disney+ and charge $22, they'd break even per each family of 4 who otherwise would've gone to the movie theater and paid $10 per individual. They would be ahead on smaller families, and behind on larger ones.
Now of course such an approach screws the theaters. But if the mass quarantines last for any prolonged period, I fully expect direct to streaming release to become commonplace. It could in fact be the death knell for the public cinema industry, even after COVID subsides.