Are we in a post-Twitter internet?

Twitter (X) clearly broke as a default discourse layer over the last two years. The replacement story has been confused — Mastodon didn't scale, Bluesky has technical adoption but limited cultural mass, Threads is engagement-positive but conversation-poor. What I want to know: is the broken thing *Twitter the product* or *the consumer-internet text-discourse layer in general*? Because if it's the latter, then no replacement will work — the structural conditions that made 2010s Twitter possible (cheap attention, before-podcast/before-TikTok positioning, journalist concentration on the platform) won't recur. Honest question. Curious if anyone thinks they see the next layer forming.