There is a palapable stigma around making new jaks and vying for relevancy. Currently, most unsucessful soyjak variants are either classic soyboy soyjaks, or cobson killers.
The original intention of jaks, being mocking soyboys, is dead, because soyboy mocking was run through and beaten to death then beaten as a corpse even more, so that avenue of making new jaks relevant is closed.
The next meta of soyjakking after mocking soyboys started dying out, is the use of jaks as self inserts. A good word that gets the gist of these jaks would be "cobsons" because cobson punctuated and defined this era of jakking. Jaks trying to be cobsons are the ones that are less made as a mockery of soyboys and more as a self insert post. Cobson style jakking started to rise up, coincidentally or not, around the time when the sharty started growing massively from sources outside of 4chan. The prospects of the heavy potential to become old 4chan 2.0, in other words, an internet phenomenon, was palpable. With cobson being at the forefront of popularity, his special brand of self inserting that took over the soyjakking meta, and controversy, there were lots of incentives to make your own bombshell cobson killer variant, thus your own mark on the sharty, thus your own mark on the imageboardsphere as a whole. Its every soyteen's dream to have THIER gem be a symbol of the sharty globally. Unfortunately, people recognize this intention, and being an imageboard, it is seen as attention seeking and assign a sort of stigma to it. This is why whenever anyone tries to cobson style force a jak that isn't very straighfowardly intended to make fun of someone, the most common reaction will be agression towards the jak. So, cobson like soyjaks, such as flartson, lennon etc.
Cobson era was also when (at least as I can recall) an overlapping era (that still continues to this day) of derivative soyjaks began. Derivative variants are variants that are derived from previous variants, that become their own things. Troonjak is a derivative variant of bernd, and is the official soyjak for trannies. (it is special because it is much older than the rest of the derivative variants) hornyson is a derivative variant of cobson, and rapeson is a derivative of hornyson, both are their own things and used for completely different purposes than cobson. Furthermore, 99% of slopjaks are derivative.
It should be mentioned that these eras are not fine lined. Smugjak is a very classical mocking soyjak of smug soyboys. However, it was born in the middle of cobson meta era. Good new jaks can be created and take off outside of their respective eras, but this is rare.
The era of cobsons is over. The culture has entered a new meta era, the current one. Coinciding with the evolution of sharty culture into total derived internal and moral metadrama, the newest soyjaks depict sexual degenerates and metadrama boogeymen. We live in the era of the slopjak. Slopjaks evolved on the booru, as a means for namefags to slapfight over SNCA. As the sharty's culture moved on to being about slapfighting about SNCA, slopjaks were naturally adopted from the booru. This is anecdotal, but a testament to the fact slopjaks are the current generation of soyjaks is evident in how naturally they "roll off the toungue" (Or keyboard? I guess?), because discourse on the site has devolved to the booru style boogeyman/namefag vs boogeyman/namefag shitflinging this style of soyjak evolved to accompany. As mentioned before, all slopjaks are derived from other soyjaks, this is by their nature as shitty low effort edits of things people found on the booru. Jartycuck is a hanging chudjak, meximutt (most original slopjak) is based on a nikocado amerimut, mediapedo is a fusion of chudjak and markiplier soyjak, etc.
All and all, the trouble new soyjaks have with becoming relevant, is that people don't realize that previous eras of jakking we like to think of ourselves by have stagnated. The current era of jakking is the era of slopjak metadrama shitflinging. The established variants are here to stay, but the time where new ones could take off has long since passed. The sharty is also in a state of decay which doesn't really help either but yeah, thats the jist of it!