Smartphones aren't nearly as good for being productive as desktops and laptops, though they're pretty good at consuming content. I think this shift away from desktops and laptops indicates a shift away from productivity.
Yes, a lot of people watched too much TV, but at least they had the capability of doing things like image editing, building spreadsheets, etc. Smartphones can do those things, but it's so awkward that it's more likely that you're not going to bother, so you're more likely to just consume content instead of create it if you don't own a desktop or a laptop.
Personally, I'm not really nostalgic over traditional computers, but I am a little nostalgic for stuff created by hand instead of filled in with a template.