There is a known strategy called EEE (Embrace, extend, and extinguish).
First, they embrace the open web. Millions of people who never would've joined the Fediverse (and, probably, don't even know what the Fediverse is) flock to Threads and start to interact with us.
Then, they extend the open web, adding features to Threads that aren't compatible with our servers. People on Threads don't understand what's wrong with our server (even though it's Threads that's the source of incompatibility).
Finally, they decide they're "having trouble maintaining compatibility with third party servers" and start to break off from us, leaving us with no way to interact with our new friends. Unless, of course, we make a free Threads account...
Google Talk is perhaps the most relevant example of this. Here's more details.
Cloanto, the company that owns the rights to the Commodore Amiga line, have a legal emulator that they sell called Amiga Forever. It's about half the price of one modern AAA game, and when you download it, it comes with about fifty games of varying notability, and there's many times more you can just install and play. And it's all legal.
I would love this to be the industry norm, imagine being able to download a NES! It's annoying that if we want future generations to be able to experience games of the past (whether to learn from them, or just for pleasure) we need to teach our children about piracy.