Latter would be too slow. Imagine all the delay of games
First, it was a joke.
Second, if doesn't have to be "too slow". Those 100 people (or 1000 or 12 or whatever the number is) get a sheet of 100 plays. Maybe it's online. Anyway, you have plays to run up the middle, run right, right left, a bunch of pass plays, etc. After every play, you have until the playclock says :35 to pick a play. Text in "77" or "33" or whatever. Whatever the software is tallies all the votes and before the clock says :33 it spits out the answer. The magic is throwing the play to the QB before the clock is at :30.
This only works for offense. If you tried to do it on defense, the opposing team would know that a hurry-up will destroy them.
It also doesn't work for any type of 2-minute hurry-up offense.
You also still need to give the QB a chance to audible.
Most importantly, this is a stupid idea because who are we - 99 other idiots and me - to think we know how to call plays better than the previous Browns coaches? (Don't answer that.)