Marshall McLuhan coined the phrase "The medium is the message" in his 1964 book Understanding Media. The idea being that the medium used to communicate the message determines the kinds of messages that can be successfully transmitted using that medium.

For example, complex, nuanced arguments are much harder to convey in the 280-character format of Twitter than with long form writing. As a result, pithy soundbites and extreme positions are what the medium encourages.

There's truth in McLuhan's phrase, but I've found it more accurate to use a softer version: the medium shapes the message, because very often people find ways to work around the medium's structural limitations.

I've noticed this happening on Twitter: people have started using Twitter threads for something that could almost be called long form content. For example, @TrungTPhan's thread on why the TV show Ted Lasso is so great, and @StanTwinB's thread on the biggest engineering disaster at Uber. These are basically long form pieces contorted into 280-character chunks.