When dealing with fractions of an inch, measuring devices ALWAYS use base 2 denominators (1/2 inches, 1/4 inches, 1/8 inches, 1/16 inches). They actually have ticks on the tape measure to represent those values. By convention, measurements are as well written down using that same principle.

It’s so ubiquitous, that people fall apart if it’s deviated from.

Also, from a practical perspective, there won’t be an explicit mark on a tape measure for any of those measurements, so they’d need to kinda fudge that if they wanted to take a more precise measurement with a standard tape measure.

In Canada at least, it’s pretty common for a tape measure to have metric and imperial units. Not sure if that’s the same on the US. In this situation, I’d just use the metric. And for any of the highlighted measurements, I don’t think I’d be to stressed out about if I mismeasured by a 16th of an inch anyways.