The Dutch and the Bird are not identical, but they are not "completely different" either. Hence, IM Watson treats both in the same chapter of his opening series.
And no one has said 1. f4 is "crazily good."
One can argue forever on whether White should press the first move advantage as hard as possible from the start or not mind particularly if the opening peters out to equality and take up the battle from there.
There are GMs who play the Colle and the London, which aren't hardest hitting openings either.
The Dutch is good enough from the black side I guess, but there's no point in trying to simulate it from the white side is illogical when you consider that there are better tries for white.
Also, the Dutch and Bird's openings are not the same thing by any means, completely different due to the tempo.
Also, the fact that the OP says that you should play it to learn how to get beaten is ridiculous, just play normal, better openings and learn from those. I don't see what's so crazily good about 1.f4 besides that it's an equal game where white created an unprovoked weakness.