1.f4 was a mistake because it enables black to choose from multiple plans that lead to being equal or better for free. It wastes white's entire first move advantage, and commits a move that black can forcibly punish by driving the game into waters where it is a weakness rather than a strength. 3 strikes, it's out.
How is f4 a weakness... does 1...e5 refute it? I don't think so. Black cannot "forcibly punish" anything, although stockfish does claim a -0.2
You have to realize that white threw away all of his first move advantage and more by playing 1.f4. Not that humans can really hard punish it, but it simply comes down to having less chances and black not having to deal with better moves.
1.f4 is just fine, and does not throw away anything.
i have not got100% ever yet