As someone who doesn't (or can't) experience the feeling of nostalgia, this is fascinating. That such a simple act of playing certain games as a kid can make someone 20+ years later experience a set of emotions that makes them yearn for that time.
For me going back to games from my childhood (SNES era) is either because they seem interesting now or because I never finished them back then (Secret Of Mana: one day I will finish you).
I do wholeheartedly agree that nowadays we are massively spoiled for choice, in both the good (holy shit there's so much good stuff that's easy to get) and the bad (financial, choice paralysis).
With the endless ethical and legal issues around GenAI, I would very much hope that Valve continues being cautious (even if it's evidently just to cover their own arses). Once we have models and datasets for AI generated game assets that are trained from entirely ethical sources (artist permissions, licences, etc.) and not just the "scrape everything and train our models from that" approach that is currently used, then maybe it could be a good thing for games. Even still, the generated assets will likely have no copyright (as is the case now), so we'll surely end up at "AI generated content flip games" flooding Steam.