I'm not a Ben & Kate apologist because its the one Fox Tuesday sitcom I don't care for, however, amongst all the comedies on Fox, NBC and ABC, something had to give. There was almost no counterprogramming, save for these networks all going against the powerhouse NCIS/NCIS:LA lineup on CBS.
I feel like some of these sitcoms would fare better on other nights and some of them deserve more viewers. They're all single-camera comedies with like minded writing, though, so it's not surprising that some of them are being sent packing.
Personally, I think New Girl, Raising Hope, the Mindy Project, Happy Endings, Go On and the New Normal all have life in them still- but they're stuck in a 23 sitcom pile up right now.