[kijin]

Different requirements.

The description contains HTML markup, such as <p></p> for paragraph breaks. CDATA is a nice and clean way to encode them without breaking anything.

The title doesn't contain any markup, and shouldn't. A good old escape function covers both the "doesn't" part and the "shouldn't" part.

[senfiaj]

What requirments are you talking about? Human readability? IMHO, RSS is for feed readers, not humans. When looking at https://news.ycombinator.com/rss , the RSS isn't that human friendly at all, all line breaks are removed. The point is the simplicity and uniformity, regular escape works well for many cases, not just description.