I tried a number of servers prior to deciding on Lich as I kept getting 'Excellent' connection to JP servers but not to NA/EU. It is quieter than most of those other servers (I occasionally log into them to compare) but there is certainly enough people to get low level dungeons done. That said, when I created my character in September I averaged a queue of 20~ on login, but I haven't had a queue now for a number of weeks.

I would guess this is more to do with the general retention rates after the trial period rather than players leaving this specific server as anecdotally it doesn't appear any less full to me, although I'm not very close to endgame yet , where perhaps it is more noticeable. The last letter from the producer stated average retention after trial is about 35% and even though FFXIV claims to have bettered that, it's still a lot of people leaving. Although it is not unexpected and built into the business model it will still be noticeable to us players I think.