You're comparing highbrow literature reviews in leading magazines to short instant messages, which are a significantly different medium designed to be read by one or two people once, and then thrown away. Your best comparison is telegram style[0], which is not dissimilar to today's texts—complete with its own slang and shorthand. Nobody's writing "u up" in the New Yorker.

[0]: https://en.wikipedia.org/wiki/Telegram_style