In its time, it was something totally different. During that era action flicks were made more. Even though QSQT was a romantic flick, it still had the action part in it with the "khaandaan ki dushmani" and revenge kinda plot mixed in. DDLJ was devoid of all that, it was just a simple, very very basic love story. Not to mention, the songs were purely amazing, all of them.
I think the fresh faces also helped. SRK-Kajol were seen before but in action flicks, and SRK was getting popular and liked at that time with Baazigar, and I guess him being in a new avatar generated a curiosity as well. Now, ofcourse it seems ordinary because many films have been made on that storyline....but DDLJ was a first of its kind.
And I know people say Sholay was this amazing film and all, I've never seen it, so I don't know...but I'm assuming Sholay was just an action flick to which worked. So similarly, DDLJ to me is comparable in that sense...because, those kinda action flicks won't probably work in this era.
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