I looked into this recently, using Goodreads data as a proxy for sales. My takeaway was that sales of these books have been surprisingly linear over time, rather than being concentrated early on: Superintelligence; Doing Good Better; TLYCS
Presumably, the trends in Goodreads ratings/reviews need to be interpreted in the context of the (considerable) growth in Goodreads’ active users over time, and for that reason, linear-ish trends in the Goodreads data actually point towards more frontloaded growth profiles for sales/# of people who have read the books?
As it happens, I did a quick-and-dirty version of this analysis yesterday—see this spreadsheet. It looks to me like Goodreads is actually helpfully aggregating ratings/reviews across editions (if you click on any one of the editions here, it shows you the same figures), and the rate at which the aggregate numbers have been going up seems to have increased meaningfully since the relaunch, which does seem to provide additional (encouraging!) evidence regarding its impact.