I think it means “This is the end of the story regarding the Towers, and the Heresy Dragon’s purpose to destroy them.” So, it was meant to be the end of that specific storyline (which was not revived in Orta thankfully), but not nessarcerily the end of the whole series.
No one in the community expected Sega to continue the series. The series was meant to end with Panzer Dragoon Saga, which is why we were all so surprised when Sega announced the development of a new game.
Smilebit titled the Xbox game Orta because the word means rebirth in Panzerese. They wanted to resurrect the series – to literally bring it back from the dead, so the name was more than appropriate.
We can safely conclude that the majority of Orta’s storyline was improvised (as opposed to planned from the beginning). However, I’m sure the creators have the potential future of the series mapped out in their collective heads.
(This post originally had different content and was not so plain and silly and pointless but it was due to me misreading a post, it’s 3am and I’m tired, sorry for the inconvenience, we need to be able to delete posts dammit :P)