His point was
consistency. When a person buys a disc, it is going to play pretty much anywhere, on ANY disc-playing device, at it's highest quality. In short,
a disc buyer knows exactly what they are getting and have confidence it can be played on a wide variety of equipment from many manufacturers. Furthermore, a Studio can't arbitrarily decide to stop by your home and yank it out of a movie collection. Etc.
"Only buy from iTunes" doesn't solve either issue. A digital version will "just work"
on Apple stuff. Go to a friend's house and that friend will need to have some kind of Apple playback hardware or you aren't watching your (not owned, but leased) movie there unless you bring along your own connection hardware.
If the studio decides to yank the movie from iTunes, tough luck unless you've downloaded a copy and stored it on something within your control. Never happens? Do a search and see countless tales of consumers whining about exactly that.
Streaming is very convenient. It offers that great advantage over discs. In exchange, one doesn't "own" their digital collection (in the same way: they can't loan, can't sell, can't will, etc), quality is lower than quality of the same film via disc, sound is up to significantly weaker than disc, compatibility is thoroughly limited to the ecosystem from which one buys and stuff like OPs issue happens.
Discs- especially in the robust used discs market- can be much less expensive than "buying" a digital version. Discs often offer the bonus of a digital download so you can own a master copy and get all the benefits of a digital version too. If not, you can make your own relatively easily (and then YOU get to choose the quality, instead of leaning on the choices of some corporation deciding for you).
All the Apple worship in the world doesn't change the realities of the many limitations & tradeoffs of digital vs. physical copies. If one can live with the tradeoffs & limitations, great. Apple appreciates your relentless patronage & evangelizing. If you do that for free, Apple really appreciates how hard you work to crown the Apple way the best way in every possible thread about
TV
But if one is able to "think different" (meaning independently of what a corporation wants you to think) discs aren't married to any one company's hardware, and one can always download or make a digital copy from the disc to get every bit of the convenience factor of owning a digital copy dropped into iTunes too.
My local library has about 2000 discs I can access for free. But they can't loan me even 1 digital movie. That's another great benefit of discs. With discs,
many entities control the media and can loan it out for as little as free with no consequence. With digital, a
single entity is caretaker of the entire collection, with complete control over that collection, NEVER accommodating any third party "owner" such as a library from loaning out their copy (too much money to be made by being a single caretaker with complete control over usage).
Nevertheless, some of us have to HATE discs- presumably because Apple says we should- but consumers do NOT have access to better quality versions of films, often at lower prices, than via discs. You won't be married to any one ecosystem. You aren't "leasing" access vs. owning (a copy). Movies won't just disappear should the ecosystem owner and some Studio have a falling out. Discs don't eat any broadband bandwidth. Discs will play even if broadband is down. Etc.
Does that mean discs are ALWAYS better? No, digital offers greater convenience. Sometimes digital versions are cheaper. Thus, there's certainly a place for them. But it's not the ONLY option. A consumer should think for themselves rather than tow the- ANY- company line... in spite of how hard any of us may work to try to convince total strangers that a single source is the one and only best source for all consumers, and that any other options (which could also be called CHOICES) are bad, bad, bad for all consumers. Caveat emptor!