Is this an issue still?
Yes. It's a bigger issue during sales, but right now there's no platform icons for the games in the weekend deal, new on steam, recently updated, recommended for you, curated recommendations, and specials boxes. (I think they used to have them?) During the big sales none of the games on the front page have platform icons.
Nothing extracted yet.
Most games aren't available for Linux, so I just end up assuming everything on the front page isn't when there's no icons to tell otherwise. I can hover over each game to show its icons, but that takes a lot of time, doesn't always work, and isn't an option on phones. Besides the inconvenience, as a developer I'm concerned this affects non-Windows sales.