The difference is that SSL, GIF, JPEG PCRE and ZLIB are extremely stable projects with very minuscule changes from version to version. Updating those libraries is rarely necessary and generally done out of convenience or just for the sake of "being up to date". I can't remember the last time a bug in one of the linked libraries made its way into a script. The last build of the JPEG library, for example, was released in 2001.. that's 7 years with zero changes.. contrast that with DCX and I'm sure you'll find a very big difference.
DCX on the other hand may update the library to introduce large feature changes or fix many (more serious) bugs, and this would not follow into mIRC until the next version release -- we're talking 6 months to a year per version, given mIRC's release history. And then, because all the identifiers would be builtin, it would be hard/impossible to override certain ones, which would completely disable anybody from wanting to use the latest versions of what *should* be an externally supported DLL.
On the flipside of the coin, if DCX isn't being updated often enough and is *not* fixing bugs / introducing features faster than mIRC releases updates, people will simply start complaining on the mIRC forums about the "DCX BUGS!" that aren't being fixed. Khaled would then become responsible for code he didn't write and mostly knows little about, which is unhelpful both to him and the well-being of mIRC, the codebase he's MEANT to support. Or how about this... what would happen if the DCX author decided to stop working on the project sometime down the line? Who would pickup the pieces? Khaled? This can't happen to one of the above mentioned libraries, because they have huge open-source support and many hundreds of thousands of applications depend on them-- ssl/gif/jpeg/zlib aren't going anywhere.. DCX might die tomorrow. Sounds more like you're asking him to inherit more work for the sake of your inability to download a .dll file.
This was all covered the last time this exact issue was raised, I suggest Searching for the discussion and reading it through so save the need for repetition.
