Is this bad to suggest that placeholder attributes can contain expected formats?

[anevins12]

What is the issue with the HTML Standard?

I was wondering whether others thought that the phrasing in the placeholder attribute definition around "a hint could be a sample value or a brief description of the expected format" is bad.

The placeholder attribute represents a short hint (a word or short phrase) intended to aid the user with data entry when the control has no value. A hint could be a sample value or a brief description of the expected format...
https://html.spec.whatwg.org/multipage/input.html#the-placeholder-attribute

By bad, I mean it can lead developers into using data requirements in placeholder attributes.

The next sentence goes on to state how the placeholder attribute should not replace the label:

The placeholder attribute should not be used as an alternative to a label. For a longer hint or other advisory text, the title attribute is more appropriate.

However, I don't think that developers will read and and think "I shouldn't use placeholder attributes to convey data examples alone", but rather "I should use placeholder attributes to convey data examples along with a label identifying the field."

We know the landscape of forms and authors do rely on placeholder attributes to communicate data requirements. It would be great if the HTML spec led by example by educating the best uses of attributes.