That kind of issue is very much "eh" for me personally. They're reading. Not everybody's motivated to read "Ulysses" or "War and Peace". Probably a significant percentage move to reading more challenging material with time.

The issue a lot of people are talking about is the decline in reading comprehension, lowered reading scholastic scores, the overall lack of reading, and the consumption of entertainment that requires little reading.

Stuff like the "Treasure Island" (#34), "Oliver Twist" (#56), and "The Hound of the Baskervilles" (#66) still rates rather high up on Young Adult literature sales by Amazon's reported numbers, even if romance and such is the top 5-10. They're reading.