There is a huge amount of FOSS that has an entire "front" web page that tells people in exquisite detail what changes have been made, who contributed, how others can get involved and what bugs are outstanding without ever mentioning what the hell the project does, or what benefits it brings the world. This just adds one more to the tally.
It's not the project's fault that the submitter/editors linked to the release notes rather than the main page.
From the main page:
"KDevelop is a free, open source IDE (Integrated Development Environment) for Linux, Solaris, FreeBSD, Max OS X and other Unix flavors.
It is a feature-full, plugin extensible IDE for C/C++ and other programming languages.
It is based on KDevPlatform, and the KDE and Qt libraries and is under development since 1998."
So, your statement about "adding one more to the tally" of projects that do not "mention what the hell the project does" is incorrect.
Though, I would agree with the sentiment higher up, that editors really should be including a brief summary on many of these things, even though I knew what the project is, myself.