In early days, the idea of cheap books on kindle was a Godsend. A book for 99 cents? Or 2.99? Readers couldn't snap them up fast enough. As I mentioned earlier, the kobo studies show that some 60 percent of books aren't even opened--so the key was to get enough sales to the people who WERE reading to create a fan base that comes back for more. (This period lasted about 5 years in my estimation--I was published during the last two. It was a very high growth period for indie sales and e-readers, especially the Kindle).
Ad sites (really Amazon associate sites)-- Books on the Knob, DailyCheapReads, ENT, ereaderiq -- most were happy to find good books and talk about them without charging. Fairly quickly, they learned they could charge a nominal ad fee and also made ad money (Books on the Knob and DailyCHeapreads STILL DO NOT TAKE ADS--they are associates and find their own bargains and choose what to talk about so far as I know).
Review sites were springing up all over the place because books were suddenly cheap, right there, right now. Many wanted free books in exchange for a review. The system was RIPE for indies. It could have been ripe for trad books too, but the trads didn't want to adapt--so they made it perfect for us.
These days, even free books elicit a yawn from many quarters (Even trad books don't get the downloads when free or cheap. I know this from my own site and tracking clicks and downloads). The cheap books? Well, they need good reviews, a great cover, good copy, AND just the right buyer.
But readers are not as enthused about reviewing books. Many don't trust reviews, but there's also a lot of sites like GR where they can leave a ranking for their own records. (Which is really a benefit for that reader, not for other readers--nothing wrong with that either!)
There are also more indies. There are also a LOT more backlist titles. All of these things change reader behavior. Seven or 8 years ago readers wanted to snap up the cheap titles before they got expensive. Now? Readers are happy to wait to see if they go on sale...
Pricing expectations are different and sampling habits are different (there's KU and SCRIBD, there's libraries delivering books online-all cheap and effective ways to read. They weren't as easy to access, or didn't exist, 10 years ago).