Have we maxed out on search? I'm not sure. I certainly seems as if some important things are not showing up. When I search on Amazon for unusual products I sometimes get very confusing results--suggesting that some suppliers are so good at gaming the results that are pushing our real objectives off the table. I expect Google and Amazon will eventually deal with that.
As Ben Evans points out in the article below, the challenge is monetizing the curated lists, given the limits of scaling up the business. Still, if you aren't planning world domination, they seem good way to grow. Assume high margin, low volume.
Benedict Evans: Lists are the new search, 2016-Jan-31 by Ben Evans
Showing every SKU, of course, is exactly the Amazon approach - 'the everything store', and it works well for some categories, and especially when you know exactly what you want. But knowing what you want is not necessarily the starting point - that's what needs to happen along the funnel. Amazon's relative weakness at curation, discovery and recommendation (I've seen data suggesting the recommendation platform is only 1/4 of its books sales) is, I think, a big reason why, after 25 years of ruthless and relentless execution, it's still only got to 25% of the print books market in the UK and USA. A bookshop (or any shop) is, yes, the end-point to a logistics system, but a good bookshop is primarily a discovery platform. That is, it's more about the tables than the shelves. And the tables are lists, not inventory.
The problem with using a list instead of a searchable database is how you get to scale - or perhaps, what kind of scale you can have.