Am I the only who feels S.A has more clean games compared to Rhaast?

Since the last patch update the meta has shifted into a tank-assassin meta. Where tanks initiate and assassins follow. Statistics followed that Kayn is actually in a good spot now with the bugfixes and Ult buffs. Also we still have interesting experiments going on in the Kayn mains reddit where people are going deathfire touch, sorc boots, Shiv splitpush and full lethality runes. (Heck even all of this shit) This champ has a LOT of potentiality and is just a box of fun.

But anyways, my question is, quite a universal Kayn main question that has been resurfacing a lot. "Why does Rhaast feel bad compared to S.A?" Maybe its the "clunkiness" that Rhaast has, or maybe its just because I just want to go fast as S.A using E

BUT, my personal thoughts to this question is that "Rhaast is NOT a reliable tank, but my allies expect me to be so." Yes, Rhaast has nice sustain, high damage and mobility but these costs items. Actually at least 3, to go in full effect of what your allies expect of you to be. (Ironically the same problem Aatrox has lol. But Rhaast has superior kits) And your allies are counting on it. Additionally your transform is around 10-12 mins.

Meanwhile, S.A kayne with the full lethality quint-marks setup with deathfires, has a high possibility to transform in 8 to 10 mins. Has 24 lethality on the start and becomes fully operational with just duskblade. Snowballing will be really fast.

As for my conclusion, I guess this phenomenon is caused mostly due to the snowballing power that S.A actually has, and also because to get your full potential as Rhaast, you need one more additional item compared to S.A.