I learned Shabbos in Yeshiva. It’s becoming more popular.
Yes, Shabbos has many Geshmake Sugyos. The whole Hotza’a with the Gedarim of Hanachos and Bassar Gufo Garir, how to understand Kluta, and one-way Kluta. The whole Sugya of Ein Mischaven and Eino Tzarich Legufo, and many more.
The Me’iri, in his introduction to Avos says that even the Geonim had this concept of favored Masechtos. Actually, we find in the Gemara, too, that Reb Yehuda was not well aquainted in Uktzin. In the end of Horios it sounds like Rebbe Gamliel wasn’t well versed in Uktzin, either, until he had to be.
By today, the purpose of a Bachur learning Gemara is to be able to understand what Reb Baruch Ber or Reb Chaim were referring to.