Meh, people who really want to bar based on dps already can. They just can't tell you, so suddenly you're kicked with no idea what you did or how to prevent it from happening again. All this would do is make it more open. Something becoming more visible doesn't mean there's more of it. We already have lots of broken parties.
On the other side, I've seen "can anyone tell me what I parsed on that one?" more often than I've seen harassment over parses with things as they are now.
But really, I think people overestimate the "elitism" in ffxiv. If you're doing your basic rotation correctly, using cooldowns, and so on, then 99% of the population will have no issue whatsoever with you. Even if you're still learning but are at least attempting to pull your own weight, people won't mind. It's the people who make the conscious decision to just put their responsibilities (whether it's dps or mechanics) on other party members that draw ire with any consistency.
And that's all assuming that it would become the standard, which itself is still hypothetical.