Just back from 9 days on Oasis -- my husband and I both had to do a bit of work every day. We had the one device each surf/stream package and it worked out pretty well. As mentioned above, switching devices is easy enough, so we didn't have any real connectivity issues. I even did an hour-long Zoom call on the morning we were docking in Puerto Rico and it was perfect.
There was just once when I needed to be on my laptop and phone, so I just signed in on one with my husband's credentials and used mine on the other.