Articles like this always paint a rosy picture of the 3270 but consider the limitations. Async style updates as commonly found on a VT designed program were tricky.

Now admittedly my own experience with the 3270 was through about three layers of obtuse IBM operating systems. Perhaps if I sat down with a 3270 and a bare OS I would consider them differently, but I always found them terribly limiting compared to a VT. More efficient sure, but much harder/impossible to do cool stuff on.

source: I was a night shift tape monkey for a IBM place for a few years. A fair amount of down time, access to a full set of manuals and an understanding boss meant I was doing more hacking on production mainframes than I probably should have been.