Re: Turtle magic
It's all witchcraft. And marketing. Equinix may have waved their wand over it, but for some, it'll always be HEX. So 150/300 would be wrong anyway. But I digress.
So the important number is usually hidden, and based on the number of decent sized carrier providers based in that building. And then how much space they can get to install their own kit. Then how many times that's been upgraded before realising there's no room to expand their own UPS kit, especially as the network kit has often gotten ever more power hungry. And then because of all that, power to the whole site has become ever more complex to manage.
So then you get cascading failures. If LINX switches lose power, peering across those switches drops. Some traffic may still go via private peering, assuming the kit on both ends of those links have power. Then there may be kit with LEDs still blinking happily, but isolated from the rest of the network because the big carrier they've bought capacity from has lost power to their stonking great DWDM boxen.
But such are the joys of networking. Core stuff went from <2,4Gbps to >5Tbps per rack, so when that rack goes dark, the impact is far greater.