Being able to respond to old posts is a good thing, like classic forums. I always hated that Reddit didn't allow you to do that, and Reddit also didn't have sort options for New Comments or Active.
Imagine if someone made a post about a tech issue, it ranked high on Google results, lots of people in the comments with the same issue, and you found the solution, but the post was too old to reply to.
But also Steam hardware survey shows Linux at only 2%, and Steam Deck I think was only half of that? So these numbers for desktop usage are higher than what Steam is seeing.