Earlier quoted context omitted.
Sorry, but tl;dr? The link you posted is deep into some drama I don't know what it's referring to.
Allegedly some actions required .net foundation to have admin access to projects under their umbrella. The foundation then changed the copyright notices to dotnetfoundation instead of the actual owners. I didn't understand the drama above the comments entirely, though.
Legally, copyright notices can only be changed by the copyright holder or their authorized agent. If someone from the DNF were to make an unauthorized, illegal change, it would be very surprising.