What kind of founding ethos doesn't allow tracking internal latency? Is their founding ethos "Never Admit Responsibility?"; "Never Leave A Paper Trail?"
This company's official ethical foundation is "Don't Get Caught."
The founder Brad Katsuyama talks about his background and motivation for starting the company here - https://www.youtube.com/watch?v=N9hoqFpDjVs
It might add a bit of color to this conversation.
From the wiki about IEX: "It was founded in 2012 in order to mitigate the effects of high-frequency trading." I can see how they don't want to track internal latency as part of that, or at least not share those numbers with outsiders. That just encourages high frequency traders again.