Earlier quoted context omitted.
A lot of those "up to"s are expressing user options, though -- "up to" 512 GB RAM means that there are configurations that include that, but also cheaper configurations that don't. That's a pretty different beast than "up to 4.3x faster performance", which means (presumably) that exactly one benchmark showed a 4.3x improvement and the rest showed less -- which is to say, means very little.
Except for the prices of course, where they use “starting at 5,499$” instead of “up to 18,299$” to indicate user options.
But for the mac pro, they would say something very obscure.
"100-120V AC or 200-240V AC (wide-range power supply input voltage)" and the maximum current is "12A (low-voltage range) or 6A (high-voltage range)".
They're trying NOT to say it had a 1440 watt power supply.