i'm only in year 11 but i would say that, bladerunner would be considered more valuable as a text due to it's context being more familiar- it is dystopic and therefore projects a 'humanoid' view of the world, also its a film and so modern audiences can connect with it on a higher level. frankenstein on the other hand (which i just finished reading, ugh) is set in the past and therefore is harder for audiences to position themselves in accordance with. hope it helps
First off, Mary Shelley was as high as one could be during the Romantic Movement and was generally considered to be very promiscuous and the Modern Prometheus of the term "loose woman." Apart from that, Shelley personally seems a little bit too ignorant of science and is readily biased on such matters (i.e. Frankenstein just magically finds "the instruments for creating life...). Beyond that, I think Blade Runner has a much more accurate perception of the impact of science and technology than Shelley's text.
Also, I think modern-day critics at least in general, tend to prefer postmodernist/ Film-Noir texts.