I think we'd likely be almost as interested in the IF as we are today if the dramatic events that shaped , and ultimately destroyed their lives hadn't happened. But would we have known about them , and been drawn to them in the first place, if their lives had proceded relatively uneventfully after the start of 1917, and all that it lead to for the IF? I think not. Their appeal, especially OTMAA's is , unquestionable, and yes, very much enhanced by the plethora of the photos they 'star' in.
But what drew us to their story in the first place? Quite obviously, the Revolution and Ipatiev House, 7/17/1918. And, of course, the latter is the basis for the possibility, the potential , for the Anna Anderson phenomenon, in the 1920s , 1930s, and even 1960s with her trials and related pub;icity, and several popular movie, play, and ultimately, book treatments. I'd be very surprised if a single IF enthusiast here would be here on this Forum, much less feeling the depth of feeling that many of us have towards the martyred IF, based solely on their history prior to 1917. As noted , the German, British, former Austro-Hungarian royal families continued in life after 1917/18. but without generating a massive and ongoing fascination and affection for them worldwide,as has been the case with the last Romanovs.
In any case, their dramatic and sad end is forms a huge part of the moral appeal that they have for many of us. I know it does for me. It's an undeniable component of their attraction, their martyrdom, the loss of beauty and innocence, not to mention the end of an era, not only in Russia, but essentially in the whole European world of monarchy and privilege.