Generics are the backbone of the domain resale industry. I think maybe you're trying to say that _keyword_ domains have lost value. To that, I might agree at wholesale prices. With end user prices on a good one-worder, all bets are off.
So yeah, you can argue that very specific product/service type keyword domains have lost value due to google's algorithm changes. But that has become less and less of an issue as people are searching less because algorithms have evolved to read your mind and present ads to you before you even search for them (facebook).
I also know from spending a million bucks on google advertising that users will click a great domain name more often than a crappy one, especially ones that are keyword based or one-word. I've ran these exact tests to compare them. The reason is that a great domain name brings authority and trust. And that's just intuitive. I mean would you prefer to click on a Sunglasses.ca ad or a BluegillsSunglasses.ca ? And because google's algorithms optimize for maximum revenue, I can actually pay LESS than competing ads to be in the #1 spot. A more attractive ad gets more clicks and earns google more money. So no matter how much you're willing to pay to be in the #1 spot, if no one clicks your ad, google makes nothing and will move you down and out. This is also why good ad writing skills are imperative - it's the same effect. Do you want to buy that new widget you need from someone who writes like a 3rd grader? Or from someone who writes an ad so smooth you're enticed to buy something you didn't know you needed?
Also, just look at Namebio. In .ca, recent sales for keyword domains of a product or service were about 1/3 of sales reported, including nice ones like snacks, finances and ticket (although some were multi-word like carcovers, etc..).
So don't give up on keyword domains. Unless I'm bidding against you, then yes, please give up