It's just their nature. Delphi version X is released. Then a couple of updates come out to fix the nastiest of the showstoppers. And that's it till version X+1. Any further bugs? It'll cost you another $2000 to see if they're fixed in the next version.
Progress in Linux is a lot more dynamic than that. "Release early. Release often."
Borland don't Get Linux and they don't Get Free Software. They tried a few years ago with Interbase and something about that scared the hell out of them - they backpedalled so fast the skid-marks must be visible from orbit.