No, this will get people to leave Mastodon for Threads in droves. Really all Facebook is doing here is leaching users away from Mastodon. The average user doesn't know or care about the "perks" of non-Facebook Mastodon instances that Eugene is talking about. They will go with the service with the most name recognition every time, rather than trust an independent, small-time instance operator.
Threads is just Facebook with ActivityPub compatibility and Facebook ads and tracking, so basically they are pulling people away from decentralized networks and back to being under their control. Then the network effects Eugene is talking about will kick in, but moving people away from Mastodon and toward Threads.
Then Facebook can quietly drop support for Mastodon compatibility. Embrace (is done), Extend (with search, advertising, and tracking), Extinguish, cut compatibility with non-Facebook instances and sink the decentralized network, then finally Enshittification.