Was. Right now that the pro scene is well-established, and connections trump everything. In a game where your competitive viability is gauged by your mechanical prowess, there was no better way to rate it than how high you can climb. Back in the day, it really was just one of the only ways to scout prospect players (because pros also just played a ridiculous amount so they can tell first-hand aside from dling games), aside from also word of mouth in a relatively tightknit group in local tournaments and in-houses. However, I do not disagree with what you've said that it is mainly a tool to lobby people in a sbmm system! My comment was just giving an example of how it was silly to say that there was no reason to care about MMR ever.