Why does Apple News+ display downloaded magazines so impossibly slow?

I have found Apple News+ to be virtually unusable on airplane flights. Even though I downloaded several magazines to my iPad the day before a flight, they don't show up unless I have an active and strong wifi signal -- and then it can take up to 45 MINUTES to actually SEE the magazines in My Downloads. It always starts out with a blank page and says that nothing is downloaded, even though I know for a fact that I downloaded many magazines. Slowly, slowly they begin to trickle onto the My Downloads page. (I have AT&T Fiber, btw, so my connection at home is very fast -- and we all know that wifi at airports is usually sub-par).

What is the problem, and why doesn't Apple fix it? The News+ App is virtually unusable like this. If you can't use it in-flight to read magazines, what is the point of having it at all?

It was so much better when it was Texture, before Apple took it over. With Texture everything loaded fast and you didn't need an active wifi signal to launch the app and see your downloaded magazines. Apple has ruined it. If I can't get it to work for a flight I'm taking soon, I'm dumping the app.

I would appreciate if someone from Apple would reply to this. I want to know why the app works this way and whether there is anything that can be done to remedy the app's glacial slowness. It's incredibly frustrating.