A nice catalogue and close-enough for a minimalist history ;-)
Maybe this belongs in metaphysics though, because of the scale you are addressing (?)

I've tended to look at these (as you note) predictable outcomes as reflecting the state of maturity? overall emotional development? OK: consciousness of the group, society or.. entire planet-full at a certain time. Well, not particularly 'I' - but ancient and modern sages put it ~that way.

Optimists feel that we are (despite all the contrary evidence) creeping along towards more general enlightenment - - - > * Difficult to argue against this, so long as the time scale is open ended; except -

Pessimists tend to believe that *THIS* is as far as this group/time gets - at least collectively. Then these add that, because of the wildly proliferating techno- knowledge + the dearth of umm wisdom (it's apparent declining ratio to increasing dumbth): there isn't time for the creep upwards to alter enough, 'in time'. We shall find one of the proliferating EZ-suicide paths. And take it. (Much like the Atlantis myth)

IIRC a yuga is ~5000 years, though the time element is only a part of the idea and (those who work in such terms) say that this yuga is, to paraphrase, about the noisiest, most chaotic one - accordingly the kind in which the several paths to 'enlightenment' are most difficult to follow. Usually the noise wins.

(Since even the concept of 'yuga' implies someone's overall knowledge of "how it is that homo-saps always behave" - I make no case for that model; the proper solution is, never mind.)

As for "starting your own" ... the problem doesn't seem to be about 'picking some Right process', one wiser? than the recent ones - it's about the limitations of the players. I don't know of anyone who thinks a 'one' can significantly alter the awareness of the mass of humanity, though certainly affecting handful is possible.

In our time, Gandhi managed a local feat and with worldwide overtones, even.. but he had to threaten fasting to death [and he clearly meant it] more than once. He alone caused foes of multi-generations.. to actually stop killing each other, for a time. But Pakistan, Kashmir still came about because they couldn't actually Do This for long. Even via Gandhiji (as both sides affectionately called him).

Trotsky appeared to comprehend the magnitude of the task, realizing that if its proponents also comprehended that it was a timeless effort - and there were sufficient of these worldwide (?) - delay was no defeat. Obviously the Stalin axis (until there was only the One left) understood as well as did G\ufffdbbels: that the malevolent manipulation of language, slander, rumor could always confound any sincere search for 'truth', let alone Truth. It still works.


So it goes,

Ashton