Don't get me wrong, I'd love for them to die and for federated or privacy-conscious alternatives to take their place. But I don't think they're all dying that much.
While it is true that more people complain and leave for alternatives than before, long term it doesn't seem like the masses are really switching yet. I feel like people are becoming more aware of privacy, market-monopoly, and other related issues, but at the same time don't want to hand in convinience, pay money to stop it, nor move somewhere when the rest isn't there yet. We see a spike on alternative SNS like Lemmy and Mastodon around the time news regarding some drama with big SNS releases, but we also see many users leave the alternatives after a time and that they never left the first platform that had drama to start with. They're just used both to eventually return. It's generally only a specific crowd that really leaves for good to go elsewhere, but not the masses.
As for the many lay-offs lately. Don't forget that during COVID the sky was the limit for tech. They all predicted that after the time being locked in our houses doing everything remotely, we'd keep doing that, and they invested accourdingly. However, as the world opened up more that predictioned turned out wrong, causing them to have over-invested and needing to make budget cuts to fix their mistake.