Nothing happened to it. It gets used by front-end developers every single day. I personally can't follow the CSS complaints. It is easier to learn than any other front-end dev language in one's toolkit.

Yeah, everyone did a really bad job of evangelizing absolute centering back in the day, leading to lots of angry Web developers and awful hacks like the inline-block/vertical-align trick. It should have been the first example given for "position: absolute"…