As the Sithicans are written as of now, there is little to no valid reason for a Sithican elf to ever leave their country. They are too apathetic to bother, or ever even want to be adventurers or travelers. One has to be creative to fine a very valid reason for Sithican to leave their homeland.
As far as their political stances goes, they are still active. (Though nowhere near to the degree of other human countries.) They do still engage in political shenanigans and have trade deals with other countries.
The notion that they just sit around and do little is very unrealistic. (as I see it.) They do still cling to their traditions, even if they have lost all meaning. They are also passionate about their superiority over all other races, including other elves. They really are not just the brooding layabouts that many think them as. What is true, is that they lack any real ambition or drive, they just continue to do so because it is what they've always done.
Though, with Soth gone, (and as the hints left on the loading screens on server imply) is that some of the Sithicans are willing to try to change their lot in life. Thus why the current ruler goes about and mercilessly puts down budding rebellions.
I have a Sithican elf by the name of Erutáron Xillen, even need questions answered or need help, just shoot me a PM.