The Gemara does hold that Sinai is greater than Oker haRim.
The Sephardi approach historically seems to lend itself to bekiut more than pilpul, hence the opposition to codification found among those like the Maharshal, famously, in his hakdamot to Hullin and Bava Kamma.
Rav Herschel Schachter. Ari Lamm, Volume 1, Issue 3).
Yet, shiurim in YU are like iyun shiurim everywhere- the emphasis is to learn how the Rishonim think and learn, and to see how the Acharonim conceptualize this, as well.
My own derech in learning is to learn Gemara with Rashi and Tosfos, Rishonim, and Shulchan Aruch with the nosei kelim, and also to learn sugyos aliba d’hilchasa/ al derech pshat, seeing how the rishonim and later poskim learned these sugyos. This is the Sephardic approach to learning and is also popular in certain Ashkenazic circles, as well.
In addition, in the same interview, R’ Schachter explains that the laws of talmud Torah were completely revamped by the first Lubavitcher Rebbe, in the Shulhan Arukh Harav, who says that the
actual text of kol hatorah kulah, consists of the twenty-four Sifrei Hatanakh, the Mishnah, the Tosefta, the Bavli, the
Yerushalmi, Sifra, Sifrei,the Rambam, and the Shulhan Arukh.