How is the ownership of this corporation enforced via the cryptocurrency?
By having all the infrastructure be self-contained the enforcement problem essentially solves itself.
The problem most projects have is there's too much external infrastructure that defines
de facto ownership irrespective of governance rules. Rules may say that group A stops controlling the project and now group B is in charge, yet group A may still have real control over the project.
Of course, we do have a website and a telegram group today, but both will be gradually obsoleted as people get Family OS (launching very soon!).
If I'm understanding correctly clients will only sync the corporation chain but not the main chain? Will it be possible to sync with all chains?
That's how most clients will operate - yes.
It will absolutely be possible to do a full sync, but we all know most won't and can't do that. Many projects seem to be in denial and base their security assumptions on everybody running a full node. For example, in Ethereum everybody just blindly trusts Infura - that's the real model. We need maximum security under
real conditions. Everything has been designed from the ground up with the assumption that people will be running minimal clients.
Is the mainnet ready?
Yes, the swap and ledger explorer interfaces already interact with the "mainnet" (there is no public testnet) and so will Family OS when it launches.