I just put my phone in airplane mode and looked at a PC I haven't viewed in months. Not sure what your issue was, I've also been in situations where I didn't have service for days and it worked just fine.Or, you know, she could have just said that:
"We're committed to continue to publish physical books".
I think she said something just like that at Gencon but not in the interview.
I too expect them to continue to publish physical books.
The app phones home and requires you connect back regularly. I found this out the hard way at a convention with terrible WiFi and cell signal.
If you consider it a temporary tool that can go away later and still use it, I think that’s a reasonable decision to make.
But it is different than the resilience we have owning physical books and knowing we or others can build digital tools based on the open licenses for 5e.
In any case the issues you raise are all about the online tools. I don't see anything that's a serious issue, in the worst case scenario the site shuts down and I'd have to buy books that I only had online.
Books are not risk free either. My house could flood, burn down or I could have my books in a backpack which gets stolen like happened to a friend. There are no guarantees in life.