Lots of cheap and even free light reading... mostly fiction with a few autobiographies & "how I became a better person" book. But very few books of substance, and very few with excellent writing. Many of the books would benefit from good editing (some have not had basic proofreading or consistency checking).
There are occasional bargains from experienced skilled authors, and certainly a few well written entertaining new works, but these are the exception. I find too many of these books not worth finishing, and am taking a break from Bookbub to seek out better reading material.