If you haven't picked up on this already, god knows I seem to sound off on it endlessly (at least to myself) I FUCKING HATE WORD LIMITS. It doesn't matter if this is "tell a story in 500 words or less" or "your story must be 2,000 words maximum" or "let's write a one page dungeon."
IT IS A STUPID GOAL TO SHOOT FOR.
And yes that is me shouting at you like a crazed subway lunatic with a drippy six-inch meatball parmesan.
Yet, at the same time, I will admit that there is no glory in splatting down words for words sake. Whatever you write, you should use as many words as you need to evoke an idea, not a word more and not a word less. As James V West pointed out, Isle of the Lizard God and The Shattered Temple are absolutely fantastic one page dungeons. They are the placemats you will find lying in wait for you under the greatest Grand Slam breakfast in Valhalla. But, if you were to play them with your friends and do it right if not rules as written you still would find yourself flipping through a bunch of books and spending valuable in-game time doing all those things that a normal adventure module should have already done for you. Both would only be improved by a few more pages of the stuff they might force me to waste time looking up.
Adventure modules are not novels. You can curl up with them for a good long read on a cold winter's night, but they are actually reference materials, things you glance at during a game. I like mine with big fat margins providing a lot of white space I can write notes in. Yes. Fat margined modules make the rocking world go round! The fewer long passages of text they contain the better they generally run. At the same time, a good adventure module should also have some substance to it. It should be there to help you create a sense of place, maybe even help you describe that dangerous corner of the world with a few florid words in (heaven’s forbid!) a text box.
If this can be done on one sheet of paper then more power to you. Otherwise, paper is cheap. Give that adventure what it needs to breathe. Murdering your darlings for the false god of appeasing the stunted attention span of the internet is just going to cause beautiful dead babies to pile up at your feet.
And nobody wants to see that.