I mean, were people really expecting any other kind of reaction?
To be honest, I was expecting it at the very least to do waaaaay better financially based on name alone but critically is going pretty much as well as I predicted. Bendis has been a hit and miss writer for most of his career and his hits and misses in this line are the Action Comics and Superman titles respectively, apparently the flaws in the latter were too much for people to take this time and (I'm sorry but I'm going full douche here), just as I initially said, the direction for Jon played an important role in all of this since most of the Superman fanbase hated what happened to him, add the fact that Rogol Zaar has been a really uninspired antagonist and the decompressed nature of Bendis' work and you simply get one of the worst titles currently.
Now that I think about it, is not that hard to believe that Bendis is doing worse than Tomasi commercially. Tomasi's Superman run had its ups and downs but Tomasi at his best was around Bendis at his best (which is Action Comics) while Tomasi at his worst was not near as Bendis at his worst (which is Superman). This era is just too erratic to be that invested in it.
It's funny, Geoff Johns is currently doing more relevant and impressive stuff with Superman in Doomsday Clock than Bendis is currently doing (and most likely will ever do) and both reviews and sales reflect that. Talent wins at the end I guess.