Having to get 3 out of 4 is huge.
Yes, but it gives substantial information to the resistance which his graph completely ignores. (Not saying that it's always a bad idea to fail the first mission, depending on your meta, etc. - only that it's not always a good idea either.)
Failures give resistance solid information. Successes give them none.
Let's look at failed missions for a 5 player game.
There are 10 possible spy combinations at the beginning of the game:
[1, 2] [1, 3] [1, 4] [1, 5] [2, 3] [2, 4] [2, 5] [3, 4] [3, 5] [4, 5]
Now, let's say players 1 and 3 go on a mission and fail. We can absolutely now remove the following three combinations:
[2, 4] [2, 5] [4, 5]
We can make a soft assumption that [1,3] is removed as well since spies coordinating a single fail on first mission may be unlikely in your group, but it's not hard information, so we're not taking it...
Failing a three player mission with one vote only allows a single combination to be eliminated. (Whichever 2 are not on the mission are not both spies.) So if 1, 2, 3 went on the three man and it failed, we can safely remove:
[4, 5]
Double failing a three player mission allows you to remove seven, or to put it more simply allows you to narrow the spy group to three combinations. If we send [1, 2, 3] and it double fails, then the two spies are obviously on that mission, and we can go ahead and eliminate these 7 combinations to leave only three:
[1, 4] [1, 5] [2, 4] [2, 5] [3, 4] [3, 5] [4, 5]
In isolation:
Values are reduced, however, based on information that the resistance already has.
But failing the first mission, while costly for resistance, does eliminate 3/10 spy combinations right out the gate.