A lot of this derives from rather raw, blunt observations on human nature and the forces that drive it.

There used to be a time, not so long ago, where the strength and agressivity of males was a matter of plain survival. A function of all religions is to define and strictly code what's beneficial to the survival of a group vs. what is detrimental (with the ensuing flaws when the systems survive too long... female infidelity was a grievous thing when people assigned magical value to blood and bloodlines. Not so relevant in the days when people can use sperm banks... it became a purely abstract "moral" issue. Same for homosexuality, a danger among a desert people with extremely low rate of survival of its offspring, not relevant anymore today, again an abstract matter of morality mostly religious believers care about).

Anyway, another function of those early cultural and religious codes was to channel some aspects of human nature and diffuse their danger. Killing your own, raping your women etc. eventually became "sins", or dishonorable among warrior people. It refocussed male agressivity against "the other", the non believers, the other tribes. We still have not adjusted to the fact humanity is now a whole tribe, we're still stuck with the more unsavoury and detrimental aspects of monotheism that define the "them" vs. the "us".

It seems to be the same sort of observations that RJ used for his AOL.

LTT and his contemporaries were probably standing on the shoulders of giants. Their time was hardly the best of their Age, they were in decline. Their ancestors had created this utopia, they were caught in it, in the phase when it was becoming corrupt and decaying.

The AOL had removed all the problems regarding basic needs. Men didn't have to protect anyone, nor fight for food. Everybody ate, everybody was safe enough and there were police for the rest. Political mechanisms were in place to avoid war, the whole concept of warfare had been eradicated.

But instincts and human nature remain, and it would be the more present as old ideals surrounding the "Servants of All" lost their meaning, when being a servant of all meant you served a little and not quite as often as in the beginnings of the Guild. It sounds like LTT's era when for the most part the system worked like a well-oiled machine, Aes Sedai were keener to mass product ter'angreal for every uses than to go provide the service in person. Less and less new uses were being developped for the OP, and more and more AS researchers skipped the simple (like Nynaeve's method to heal severing) to venture in the overly complex, abstract and esoterical... vacuoles, mirror worlds, drilling holes in the pattern and so on. The Guild wasn't called in the fields with the Aiel anymore, someone had made Nym for that. Aes Sedai more and more devoted their talents to pointless ventures, overly complex engineering feats etc.

So yeah, you get the feeling in LTT's time there were the masses of AS, a lot of them like Balthamel/Moghedien were totally wasting their talent and rarely called upon as there was nothing to do - nothing the Guild still had the drive to put in motion anymore, too busy with the internal competetion, and the Guild clique who had turned their greed, ambitions, aggressivity, desire for power into this vast contest for status and power. Shining in that society must have been exacting indeed, but also similar to what drives financiers to amass fortunes in hundreds of billions, far more than they and everyone they know could spend in a lifetime for personal use. They could stop, and spend their best years of life doing other things, in complete freedom, but they don't.

And yeah, the White Tower and it's Ivory Tower and apathy with the OP hardly seem unique, they were the heirs of the late AOL guild. They had a brief rebound with the WOS, but almost entirely devoted to devising ways to destroy with the OP, stuff the post-breaking AS turned their backs on. They had lost a lot of the work of "giants" that preceeded the time of LTT, but they inherited a great deal of the apathy of the AS of LTT's time, and a lot of their culture...

And yes, it's not too surprising 50% of the AS eventually joined the Shadow. And I suspect at first the really strong/succesful ones were rare among the Chosen, mostly it was the masses unable to shine in the Guild, the lazy ones, the bitter ones etc. until the Shadow became strong enough to start to attract some of the ones vying for the top positions of the Guild or their fields but who couldn't reach as far as they dreamed of... the Barid Bel Medar for instance, who's gone where LTT wouldn't follow to outshine him.

The more the series progressed, the less LTT appears to be "squeaky clean"... arrogant to the point of considering himself the pinnacle of his Age (a flaw common to many of his time, it appears), divisive, terribly stubborn and full of himself, overly ambitious, probably extremely sensitive to the slightest mark of disrespect, and if we go with Moghedien's comment (or was it Graendal), he was also insufferably sanctimonious about the cosmology (which recalls most Elan Morin). He wasn't a terrible man, we've seen much better aspects of him too, but he was no white as snow hero either.

The irony is that a few channellers of this time like Nynaeve might have outshined most of the AOL AS with the same education... but probably not had they been raised in the culture of the AOL... the whole AOL society had removed most of the impetus for the AS to shine in what would have really mattered, too busy creating the most amazing Virtual Reality ter'angreal that would flabbergast everyone at the fashionable social spot to be seen at that week, if you had the status to be allowed in.