also not stated (that I could find), can you watch that any time after or is it only something like a 2-day window to watch?
You get to watch it for as long as you subscribe. From https://www.theverge.com/2020/...
The $30 acts as a purchase — as long as people subscribe to Disney Plus, they’ll be able to access the film.
So...it behaves sort of like a purchase...you can watch it as much as you want as often as you want for as long as you keep paying for the Disney Plus subscription. Yeah, this isn't really a purchase...you can't resell it and you have to keep subscribing to keep watching... but it doesn't have a definite time limit
So, depending on your perspective it's not a bad deal. Movie tickets for a family of 4 would be $30+ by themselves, plus you can pay at-home prices for the popcorn, sodas, candy, etc. On top of that, you can watch it as much as you want for as long as you're subscribed to Disney Plus and can avoid having to buy the blu-ray or digital versions, saving $20 or so later. For a family, it's a very good value when compared to a night out at the movies...and many families will just always be subscribed to Disney Plus for the next couple of years or couple of decades because of their kids.
If you're a couple out on a date-night it becomes less of an obvious value...$30 would be about the cost of two movie tickets, but depending on the couple they may prefer a night out vs. a night in...some people prefer the theater experience of the large screen, impressive sound, etc.
If you're just a single person wanting to watch the movie on a Saturday afternoon with nothing else better to do, it's not a great value...$6-$8 for a matinee ticket (depending on where you live) vs. $30...and you'd only likely want to watch the movie once anyway or are perfectly content with waiting to watch it again until it comes to one of the streaming services under their normal offerings...or are fine with the $5 on-demand pay per view to watch it one time.
There are some groups like my self who make movies more of a social outing...we all go out and watch the latest Marvel, Star Wars, DC, etc. Blockbuster hits as a late afternoon matinee outing. We socialize lightly before the movie and then go to dinner someplace after the movie and discuss the movie and/or whatever...The movie is an excuse to go out and hang out with friends....For us, we likely wouldn't get the $30 streaming movie because it doesn't fit how we consume movies.
Some people would want to watch the movie immediately when it's released and want to AVOID the movie theaters...full theaters, sticky floors, obnoxious feet on the back of your seat, people using their phones, overpriced bad food...for them, the extra cost, effectively double price of a movie ticket, to avoid those annoyances/hassles may be worth it to them.
Ultimately, it comes down to a value judgement. What something is worth is going to be unique and individual to each person...ESPECIALLY for intangible goods or services...like movies. It seems that Disney is throwing another offering on the pile of ways to consume their content. So long as they continue to offer the old ways, it can only add value and options to the world.
Disney is merely reacting to the changing market. Another change in how the world lives due to technology. I think this was going to happen eventually anyway...where movies are initially streamed for a premium at launch and then lowering in price as time goes on. Very similar to video games...$60 at launch, then $40 a month or two later...then $20 6 months or so later...then Steam sale for $10.