I'm actually upset that no one has recommended this yet. Some major points of similarity as both have:
- non-blood-related siblings/???? (childhood sweethearts) turned lovers trope
- banter (except I think Sweet First Love's is a lot better) between the leads
- a lot of romance which makes it perfect for mindless binging (more so in Exclusive Fairytale in my opinion)
- school life and uni life (although there's more school life in Sweet First Love)

However, if you haven't watched both and want to know which one's more suited for you, Exclusive Fairytale is 1000% romance-centered but has none of the stereotypical misunderstandings or jealousy. Whereas, Sweet First Love has sparks flying everywhere that is on an incomparable level for me, and it contains quite a bit of jealousy from the male lead, but is so cutely executed. It does also have a little bit more plot development than Exclusive Fairytale.

Similarities:
- Both are related to cpop performances and are female-only (Youth With You series does have male-only ones too in the other seasons)
- Famous cpop celebrities that act as mentors/leaders, such as Cheng Xiao from WJSN (and acted in Falling Into Your Smile among others), and TEN from WayV in Great Dance Crew, and Lisa from Blackpink and rapper Will Pan.
- Both are survival type shows, where people get eliminated based on their perfomances.

Differences:
- Great Dance Crew puts a focus solely on dancing, while Youth With You is based on the different aspects of the cpop industry, such as dance, rap and vocal.
- I personally think Great Dance Crew seems to be a lot more relaxed in comparison to Youth With You, which is a lot more formal.