aside your delusions of omniscience, are the myriad changes that have pervaded the entirety of the game since anyone last competently played a lich.
Sure, the numbers in the past far exceed what CF typically pulls today. And I would also agree that the big gangs that brought down said skilled liches were comprised of more players than liches face today, whereas today's liches face classes with a wider variety of skill sets. They also have an anti-gank code protecting them. However, the vast reduction in player numbers more likely reflects a loss in more than merely the bad players, as you seem to presume, and instead reflects a loss in total players of varying skill sets, from horrific to incredible. You presume that the player skill has somehow dramatically increased in the absence of those less skilled players, or that only the skilled players remain today. I don't really think that assumption has any foundation in reality.
I've read plenty of lich logs. I've played for a very long time. I've seen many people come and go, and yes, I have no problem admitting that weaker players tend to disappear more quickly now than before, due to the increasing complexity of the game, resulting in players of some skill being able to stick it out more than their counterparts. But I certainly do not think that the skilled players today outnumber the skilled players of the past. If anything, there's simply less garbage, making it appear like those who do play are particularly more skilled than the larger hero PK ranges of the past.
That garbage played a vital role in the demise of more than one lich. Read the logs.