But is it USB-IF’s fault manufacturers tried […]
Yes, it absolutely is USB-IF’s fault that they are not even trying to enforce some semblance of consistency and sanity among adopters. They do have the power to say “no soup certification for you” to manufacturers not following the rules, but they don’t use it anywhere near aggressively enough. And that includes not making rules that are strict enough in the first place.
A typical project manager will get a range, take the lower bound and communicate it as the only relevant number to every other stakeholder. When that inevitably does not work out, all the blame will be passed on to you unfiltered.
Depending on where you work it may or may not be worth giving someone new the benefit of the doubt, but in general it is safer to only ever talk about the upper bound and add some padding.