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  1. People would rather consume a 30 sec thread about nothing and move on than read a 10 minutes post that might be about nothing. The cost differes.

Yes, after all, money-making and content-making have all come together to calibrate your time management as well. Time is a scarce commodity. In that context, people will be increasing becoming smarter.

1/ Exactly humans are always driven by expediency. The tokenized society will make you drive more like that. And in the category of long-form content, anything beyond 900-1000 words is even counterproductive......

2/.... because that will chase the readers away unless it is of specific interest.

The only people that should be making 900+ post are fiction writer. I don't care whatever you have to say but I am only reading a 500+ article if I want to learn something new and not listen to someone's opinion. God forbid!

Expediency, time management, etc are one part, but can we say that today's generations are averse to long-form content with the rise of Twitter-like media?

Yea. Short form content has messed with our attention span.
Long form content has become a laborious chore no one wants to engage in aspect if utility is guaranteed.