Should owners of private companies pay Zakat to the state, or should they distribute it themselves, knowing that they are accustomed to paying it to those in need?

If the state distributes zakat (definition) to its rightful recipients, then paying it to the state is better, as it possesses information about the poor that individuals do not. However, if the state does not distribute zakat to its rightful recipients as required, then it is not permissible to pay it to the state. And if there are individuals who do not receive their entitlements from the state, then it is permissible to allocate a portion of the zakat to them.