I still mourn the shorter format. It forced people to use Twitter more like feed of links and events, which makes sense as it was competing with the open standard RSS and Atom at the time (more specifically popular feed readers using them).

With longer content, media and replies added in, it started closing itself in a bubble and becoming about Twitter being its own thing walled off from the rest of the world, a concept significantly different than Twitter started as. Maybe it also seems more monetizable, but there can be a debate on this.