What is better, ICBM gambit, or King gambit?

At 210 elo ppl may easily play complete trash, invalidating any "gambit theory". Simply play solid opening, gain advantage and win without having to sacrifice anything.

The King's gambit is a real opening that while dubious has no refutation, whereas the ICBM gambit is an internet meme out of the Tennison gambit. If you land the ICBM you'll win the game but if you want to play some real chess go with the King's gambit.

Both are bad, but King's Gambit less so.
Is the King's Gambit "bad"? Based on what?
Sure, it doesn't give any advantage to white, but neither does any other opening.
Also, it isn't played regularly at the top level, but that's more a fashion thing than anything else. Openings come and go, the KG will probably have a time to shine again some day.