Indeed. IRC is closed federation and the server admins are in a great position of power. In an open federation like email or matrix, the power of server admins is much smaller, and this kind of takeover wouldn't happen. Or if it did happen, it would be less of a problem.
This freenode thing shows they have less power than they think. If they abuse it, it's super-simple for their users to move elsewhere. Every sane client supports connecting to multiple networks at the same time.
