If you draw this hand, your opponent has zero ways to respond, and the game is no longer fun.

Of course, that's the joke. The only winning move is not to play.

There is a meta-joke in that there are a few ways to respond to this, but only if you know it's coming. @SkyezOpen@lemmy.world responded with one. If your opponent also has a way to get fast mana out, a simple Lightning Bolt will also do it if it's inserted between your Channel and Fireball. Or anything that counters your fireball, which will leave you standing there with your pants down around your ankles, 1 life, and probably an empty hand.

Then the meta-meta-joke is if you are known to be packing this combo, people around you will deliberately structure their decks around countering your stupid 1 turn win (if they will even allow you to employ it at all, given that Black Lotus is very, thoroughly, extremely banned specifically because of this combo), but this requires making sacrifices to their usual strategy and then you can show up unannounced with a different deck instead...