The W3C maintains an excellent list of all CSS properties, both current and proposed. Of the 115 properties marked as CSS 2.1, sixteen of these are not part of any CSS module (for level 3 and above). These are:
Let's take one example, I suspect by far the most commonly used of those listed,
This section is being rewritten. Refer to section 10.8 of [CSS2] for the normative CSS definition or the 2002 Working Draft if you want pretty pictures. (But ignore the old text, half of it’s wrong. We’re not specifying which half, that’s to be determined.) The CSS2 specification should be used as the guideline for implementation.
So it's not deprecated, it's just that the description from level 2.2 holds until such time that a level 3 definition can be written. Level 3 is huge, and work has to be prioritized. Line-height obviously works well enough for that priority to be low. No doubt, it will be addressed eventually.
The others are probably similar. Their level 2 definitions have simply not yet been superseded.