I did a Zoom depo last year because we were an ancillary party and the client didn't want to pay for us to travel/stay overnight for it. It was fine. Other attorneys in the office have had pandemic Zoom depos. Some have been really difficult, especially with exhibits. Lots more logistics involved.
The App. Ct. oral argument by Zoom would be interesting. Given the small delay, the interrupting questions could get awkward. It also seems like, other than the judges on the bench, it would be easy to socially distance for that and do it in person.
The deps have been pretty pain free so far. These are all expert deps and we have an agreement that the SDT rider response will be made 10 days before the dep, then we send the exhibits we intend to use to counsel at some point before the dep so the deponent can have them at hand. You give up the element of surprise, but where experts are concerned, that's largely TV stuff anyway. I have 3 deps next week, all experts, 2 by Zoom and one in person.
The oral argument wasn't too bad. When the judge has a question, if there is not a natural break, he puts up his hand to interrupt the lawyer (which was necessary more than once with my partner....not entirely sure he inhales during arguments).