Perhaps the writer misses their 20s now that they are 35, like almost everyone.
So (for me) it's not just a downward slope where older = better as I become crankier, it's that some particular services at some particular points in time hit a sweet spot that others didn't. For me, important qualities are protagonism of text (networks with protagonism of images like Fotolog or Instagram are posturing tools, as the author says), thematic groups/channels (I like to discuss topics like politics, philosophy, videogames, learn languages, etc.), and ways to actually meet people (MSN didn't have this).
Facebook was great in its peak as it ticked all these boxes, with the added value that you could find real-life acquaintances and follow them - no social network has ever been that strong at letting me know about my old classmates' weddings and children, which is a cool thing IMO.
Today, the widespread social tool that comes closest to my ideal may be Telegram groups, but the discovery and meeting people part is only so-so.