The StoryGraph looks like yet-another-silo in the merry-go-round of social reading sites. I prefer IndieWeb solutions like Gregor Morrill‘s (@gRegorLove) https://indiebookclub.biz/, an app/platform that posts your book reading data and updates to your own website.
Tagging Tom Critchlow (@TomCritchlow) and Ton Zijlstra (@ton_zylstra) for their thoughts and maybe an update on any recent experimentation.
I do wonder if StoryGraph are planning on making the ownership of your own data on your own site easier? That might be a reason for some buy-in.